BAD_POOL_CALLER and IomDisk.sys

Rants37 Comments

So I thought I would buy a 2nd hard drive to store media files on because mine is filling up.  So I bought a 200 GB one from Dell online.  When it gets here I find out that most computers have a 137 GB barrier and you have to use a special disk controller card (included) with it to get it to work in my computer.  I am out of slots so that won’t work.  I returned it.

So I go back up to Dell’s web site to buy the same 120 GB WD drive I already have and there are no hard drives on  I called and they said they only put specials on the web site and I could pay $250 for the drive.  No way.  So I go to and they aren’t accepting online orders because of a web site revamp.  Amazon is sold out too.  Circuit City finally rescued me.

So the drive shows up.  I stick it in the computer.  Its all configured correctly.  I start into Windows XP and I get the blue screen of death with the error BAD_POOL_CALLER.  What the hell?  I do a Google search and nothing related turns up.  This is some generic hardware error.  Man, this sucks.  So I took out my primary drive for testing and put just this new one in.  I was able to format it and use it just fine.  But now I need both to work.  I tried everything else I can think of.  I even have two different cables on the disk controller so I tried with 1 drive on 1 and 1 drive on the other.  Same thing.  Found a BIOS update.  Didn’t help.  No disk controller driver updates can be found.  I even took out all the cards I added since I bought the system just for fun.

I called Western Digital and they said “Your drive is not the problem.  Call Dell or Microsoft.”.  Great.  At Dell, they don’t know how to use their phones to transfer people.  Anyway, I worked with a 1st level tech for a while who felt my pain.  Nothing.  But of course since my system is out of warranty there isn’t anything else they can do.

Man, now what?  I am stuck.  Can’t get this thing to work.  Maybe I will just put it into one of my other computers and make that the file server or something until somebody figures this out someday.  I put it in another computer and it worked fine as a dual.  Something is up with my system.

So its 1 AM and I am not tired and I will not be beaten.  For some reason, I was looking at my Windows 2003 server driver versions and needed to compare something with my XP machine that won’t take the hard drive.  I notice on the XP machine that there is this file called IomDisk.sys from Iomega randomly bound to that drive.  Its a driver…hmmm….I don’t know what it does…hmmm…its not signed…hmmm.  I googled it and found some weird HP thread that talked about getting rid of the driver because its was messing up all kinds of shit.  So I thought – what do I have to lose?  I purged my entire system of this file.  I went through the registry and cleaned it out.  Mostly stuff under the HKLM Classes key (search for iomdisk).

So I put the drive back in.  Reboot…and…..Windows XP screen…good….progress bar going…good…..USER LOGIN SCREEN!  I have been redeemed!  I don’t get it but its fixed and I don’t care.  Its 3 AM right now and I can finally go to sleep.  Task completed.

Iomega …. burn in hell. 

Sometimes I hate computers.

  • Amy Thompson

    I can feel your pain, but it is a good thing that you don’t have a “punch-the-time-clock” type of job!! Have a great weekend! Amy

  • yeah dude, I would have told you that. 😉
    Maxtor was the first to break the 137 GB barrier about 6 months ago with their 160 GB drives. then WD came out with 200 GB hard drives, then Maxtor decided to come out with 200 GB HD’s too except that theirs came with the controller card included. you were lucky to get the Maxtor because WD’s 200 GB drives don’t come with the required controller card.

    thats why you need to build your own system dude 😉 the new motherboards have these ATA/133 controllers built-in. 😉

    oh, and to prevent any future worries, be on the lookout for ‘serial ATA’ drives, they will be coming out next. 😉 serial ATA is the new standard that uses a USB type connection on the motherboard instead of a standard ATA. so far the benchmarks aren’t much better then ATA/133 so I wouldn’t bother getting one at this time, but thats whats next dude 😉 then a new standard for RAM is coming soon too dude, gotta keep up. hehe

  • My disk controller is built in. Its the random Iomega driver that was the problem. You didn’t know that.

  • eburke

    dude, get a firewire/USB2 external drive. makes things MUCH easier!

  • Vinod

    Recently i purchased a computer with intel D865 Mother board after loading windows xp Some times it is showing BAD_Spool_Caller please help me to find out the problem…

  • You are on your own, dude. No clue.

  • cory

    hi i have same problem bad pool caller i got it wehen i firast built my computer and i only have 1 200gb hd and now 2 months later i had to reboot my pc and i got it like 3 times. i just did a search and my computer deosnt even have the iamdisk.sys and i still have that problem some say it could be video card but i have a powercolor ati radeon 9600pro 128mb video card.

  • cory

    hey vinod i had that problem when i built my computer then had no problem for 2 months now all of a sudden i got it again 3 times. all i found on net about it doesnt make sence as its about upgradeing which we didnt do not sure either

  • tanos

    Hi to all

    I also have a problem with BAD_POOL_CALLER.

    I’m running win2000 SP4.I have a 80MB sata seagate but haven’t add any hardware recently.Suddenly a day it started to give me this error message.I’m not able to reproduce the sequence in which it occurs but it seems to happen only when i’m online.

    Any ideas ??

  • D.W.Roberts

    Sometimes it’s caused by a third partry firewall running while the XP-provided one is still live.

  • tanos

    But i’m running win2000 and as far i know there isn’t a firewall built in win2000 !!

    I have installed and running zonealarm pro at which i doesn’t made any settings modification since i installed so i dune it cause the problem .

  • tom

    Your long night have cost me only a half an hour thank you

  • I just got bad_pool_caller when trying to view a somewhat bugget avi-file with DivX playa… I’ve also gotten it at somewhat random lately. My newest disk is a 120gb one, don’t remember the brand right now.

    My graphics card is a GeForce 4 Ti4200 8xAGP running the latest nvidia drivers (i think)…

    Can’t find any decent info about what this “Bad_pool_caller” is, (and why he’s so bad at calling for pools… =P )

  • Wes

    Same story here folks.

    I have just built a P4 3.06 Ghz system with 1Gb TwinX Corsair 3200 RAM, 36Gb 10000rpm system drive, 91Gb 7200RPM Video Drive. I took a Generic internal modem out of my old machine and and installed it into my new machine. When I try connect to the net or query the modem in Device Manager, I get the Blue screen BAD_POOL_CALLER message Any ideas?

  • shaun

    I too have recently started getting the bad_pool_caller error, and I am thinking the issue may be power supply related. I have a P4 3.0 Ghz HT, 1024 mb ram, 160 gig hd, GeForce 5500 256 mb ram, and a 350W PSU. Store bought with a few personal additions. Have only had the computer maybe 2 months, and have stressed it daily, but in the past couple of days I started running some very resource intensive programs. Thats when the resets began, and only when I disabled the auto-reset did I see the bad_pool_caller error message, and now its to the point when I can’t even run minor programs without pulling the error. I have discovered that even a moderately equipped system can push 355W of usage, and with some of the systems posted here, I doubt if the PSU going isn’t to blame for a good percentage of the errors here, especially on anything bought pre-assembled from a large retail source, such as Best Buy, Dell, or the like.

  • paul

    Bought a new dell got the same problem, only a month old is it dells problem or mine?

  • Hello from Cairns in Australia.

    Well, I am afraid I can’t shine any light on this one either.

    I have a system that was running well on Win98.

    Put a new HDD and DVD R/RW in to it and start loading XP.

    Most of the way into the load , up comes the wonderful BAD_POOL_CALLER.

    So, I try 2 different hard drives, unplug the DVD and start loading with the CD ROM. Changed the RAM over.

    Like most of you, I am at my own tripping out point.

    I am about to take out everything but the bare essentials and go for a fresh load of XP. Maybe it is the DVD R/RW?

    I did go and check our pool, and it has a lot of leaves in it, but thats the closest I’ve got to making any sense today.

    Of course, this is a customer’s computer and they want it in a hurry.

    Ho Hum, another sh%&*ty day in Paradise.

  • shaun

    Well I finally figured out what was giving me the BAD_POOL_CALLER. Turns out my recently installed soundcard drivers were not Microsoft verified, and for good reason. They were the supposed correct XP drivers, but XP did not like them. So I replaced the c-media soundcard with a soundblaster card from a second computer, installed the updated drivers for that, and the error disappeared. So, the moral of the story is that the market standard brands are the market standard brands for a reason, and that unsigned drivers are unsigned for a reason.

  • John Doe

    I upgraded to windows xp pro 2 days ago, i usually leave my pc on for extended periods of time, and i have not installed any new hardware recently. I am currently using a 30 gb harddrive and i dont have any fancy shmancy video or sound cards….so why the heck am i getting the blue screen of death with a bad_pool_caller error???????? Win XP blows chunks I am going back to win 98.

  • shaun

    John Doe:

    You kinda answered your own question there. If you upgraded to Windows XP, did you upgrade all your drivers to their XP versions as well? If you didn’t, you will get bad call errors for any drivers not compatible with XP.

  • Doomsday

    The BAD_POOL_CALLER problem it seems, can relate to drivers, software or faulty hardware. If you search the MS site you’ll find a lot of techy info about it but little about resolving the problem.

    It’s important to note the rest of the error message i.e. the three parameters after the message as they (especially the first one) can help to identify the problem.

  • Zarnywoop

    My (windows XP Pro) computer has been running like a dream for months and months I’ve installed new sound and graphics cards alsorts of software. No problems.

    For a long time I havent had my Epson color 640 stylus printer installed (its an old printer I had when I got my Win98 computer 4 or 5 years ago) I’ve just not needed to print anything and if I do I just use the other computer which has a nice new printer on it.

    Anyway, recently I’ve been needing to print off single pages from the web so instead of copying it to disk and then moving to the other pc, I decided to install the drivers for my printer.

    The Epson website says that the drivers are Win2000 and XP. But when you install them it says that they are not for XP and could cause instability. I continued since Epson say they are ok for XP. That was yesterday. Just now I get the BAD_POOL_CALLER BSOD and a quick search lead me here and to other sites. I’ve uninstalled the drivers since I believe that was the cause of the problem.

    It appears a lot of you have Windows 2000 or similar or you’ve updated something so if you are having this problem…. make sure your drivers are good and installed correctly etc.

    I would say its always best to start a new OS on a clean install. You should consider that and make sure when you update drivers or install new ones that you remove all trace of the old ones becuase it can and will cause conflicts! Use DriverCleaner 3 which is free.

    Unsigned drivers are ok to use. Graphics/sound card manufacturers update their drivers so quickly that it usually isnt worth getting them tested by Microsoft and having them signed since the next update will have arrived long before MS gets around to testing them.

  • Kelvin

    Well I’ve just had my new Dell PC delivered last night and just had my new cable connection set up… and it’s damn nice if I do say so myself (Sydney – Australia).

    But I have had no less than 15 blue screens since then for a variety of reasons, “BAD_POOL_CALLER” being one, another being something about “USB” (can’t remember the entire message), … and probably some other ones thrown in for fun.

    They’re apparently going to replace my motherboard and processor. I have just switched off the Windows Firewall due to an above comment as I had both that and McAffee going at the same time, so here’s hoping…

  • Kelvin

    To follow up on my post last night, after an enormous amount of annoying blue screens, and very little assistance from Dell tech support, I found an obscure sight on the Internet that alluded to problems with processors with hyperthreading and conflicts with USB devices, specifically cable models.

    I have now disabled hyperthreading and it has run perfectly since.

    I today have purchased a network cable so I can use ethernet instead of USB, which should alleviate all of the problems and enable me to enable hyperthreading again, but it remains to be seen whether my USB wireless keyboard and mouse will pose a problem.

    Apparently when hyperthreading is enabled the problem results from too many threads being simultaneously active – i.e. the usb modem creates a lot of threads during the process of sending and receiving data. Once the thread limit is reached a stop error occurs.

    I am not so sure on this myself but I imagine a wireless USB keyboard and mouse operating would create a similar amount of operations and again potentially result in stop errors (I did have some stop errors prior to installing the Internet, but only one or two).

    Hope this helps someone!

  • bruce

    I getting the same BAD_POOL_CALLER crashes however it sounds like Windows XP might be the problem. It’s the common thread in everything I’ve read so far.

  • Ed
  • Not Happy

    Had XP home on a AMD 2200 512ram a DVDr CD+-RW

    and a DVD+-RW. Upgraded to a Sony DRU800A and

    machine started resetting constantly finaly got to point where it would reset as soon as boot.

    Yanked hard drive put new 250 G MAXTOR in and tried installing XP PRO. Started coming up with a thread error. So disabled all Plug n Play,Cashe L2 tried installing XP pro again and it gives me the bad_pool_error and every now and then resets. Any ideas?

  • shogo

    have you tried hitting it?

  • Bad_Pool_Caller and Windows XP repair. I have seen this error a number of times, but only on Dells. A fix I have found (50% success) is to remove all PCI cards/ secondary drives and go into the BIOS and disable anything that looks like it would require drivers (onboard sound, LAN, etc). Restart the XP reinstall and it works, but not on every machine.

  • John Osbourn

    I just fixed a computer that had this come up, I pulled the RAM and tried one stick at a time and found that one was FUBAR. Trashed it and put in a new DIMM 512 and it works just fine.

  • Jono

    Bought brand new HP AMD notebook. Turned on, went through First Boot screens, first thing after booting the Security Centre pops up saying the preinstalled Norton is out of date – so I click on it to activate it. System freezes. Reboot, uninstall, try installeing AVG free, fails, retry – works, uninstall Acrobat 6, try installing Acrobat 7 – fails, rety – works, install OEM Office, fails, retry few times, works. start detecting updates, quick blue-screen – didn’t see message – disappeared.

    Tried reloading all drivers and software (nice automatic program) – gives an error.

    All crashes and errors sent to Microsoft – every error says “no known solution to this”.

    I put in System Recovery CD, rebooted, formatted hard drive, (full, not quick), it started “copying files” – did not get to installing files when BSOD – BAD_POOL_CALLER 0xC2 comes up.

    NO drivers loaded, NO XP loaded, and still BSOD!

    System is AMD Turion M40, 1GB RAM, 80GB HDD.

    2am, customer expecting system to be built and ready in morning… somehow I think not.

    After reading these other posts I’ll try disabling hyperthreading (if AMD Turion has such a thing and it can be disabled in BIOS). Least then customer can use it until warranty replacement comes.

  • Charles Manson

    Dell computers are a problem and I found the BAD_POOL_CALLER problem disapeared after I threw it in the pool.

    The problem with the Dell hotlines are that the people on the other end are from the same towns in India where US pharmacutical companies are running tests on the general population

  • Tazmouse


    I Have a “new” (4 months old) Dell XPS 400 running XP home. 250 SATA drive, 1G mem. Got the BSOD, it WILL NOT allow me to reinstall OS, boot into safe mode or anything else. When I try to reinstall the OS from the Disk that Dell sent it just keeps getting the Bad_pool_Caller and stop message along with missing or corrupt windows\system32\config\system. I have had nothing but problems with this machine since I bought it. I’ve had to call support 4 times for weird stuff, like out of nowhere I no longer had access to my dvd or cdrom drives. They just disappeared. The software that came with it wouldn’t reload. Then their preinstalled version of Mcafee puked for some reason. I’ve built several computers over the years and have abused them severly and never had this much trouble. Anyone else have problems with dell PC’s?

  • No Gamer

    I am not a gamer! I have a Toshiba 60GB, XP Home with 512 Mem. I got the BAD_POOL_CALLER after I installed an additional ISP. It seemed that the two ISPs were not compatible.

  • Randy

    Steven Hopper, your post really helped me out, I’ve been struggling with my computer forever and I removed all pci cards and disabled all on-board periphials; Sound/video/usb and Finally It worked…thank you so much!!!!

  • ace

    hi guys…

    i also encountered this BAD_SPOOL_CALLER error just a few hours ago when i tried to install XP. What can be causing this problem? Can anyone help me pleeeaaasee? Thanx.

  • Hello,

    Even though the original post and comments are now four+ years old, I still found useful information here. I work in tech support and this has saved me a lot of time and looking around. Thanks a lot!

    …and you’re using reCaptcha! Excellent!