DRIVER_IRQL_NOT LESS OR EQUAL(kbdclass.sys)

[jak5]

After (I believe) a Microsoft update I get the BSOD with the above error, (DRIVER_IRQL_NOT LESS OR EQUAL(kbdclass.sys)) I have rebooted several times and cannot log in directly at the machine, however, I CAN log in remotely and rune it that way, Would rather not! Any help is appreciated!

[Malygris1]

Hi there @jak5,

Welcome to the HP Support Forums!  It is a great place to find the help you need, from other users, HP experts and other support personnel.  I understand that after an update your computer is starting with a BSOD. I am happy to help with this.

A quick thing to try is a System Restore to roll back to a previous system configuration. HP PCs - Using Microsoft System Restore (Windows 10, 😎  If necessary you can try to access System Restore from within HP PC - Windows Safe Mode (Windows 10, 😎.

If that does not help at all, then please post the full product number of your computer. See the following, if you need help with that information. How Do I Find My Model Number or Product Number?

Please let me know whether that works for you, and if it does resolve your issue, please mark this post as a solution. Kudos would also be appreciated.

[jak5]

Unfortunately, when I tried that te only roll back I could choose from was the one with the latest uates so -- no go. The product info is:

Model: 700-414

Product: J4V91AA#ABA

S/N:[Personal Information Removed]

OS is Windows 10 Pro. The first thing I did was upgrade to 10 Pro from 10 Home.

JAK

[LarryMeBoy]

Leftover wrkrn.sys from a prior Webroot installation was the culprit causing "DRIVER_IRQL_NOT_LESS_OR_EQUAL(KBDCLASS.SYS)" after I installed a Microsoft 5000 Comfort Keyboard and Mouse. I am running Windows 10 on my HP h9-1170t desktop computer. I uninstalled Webroot Secure Anywhere several years ago but evidently Webroot left a file called wrkrn.sys and it remained active and running. I used regedit to find and delete any keys with the name wrkrn.sys. I also deleted wrkrn.sys from Windows --> System32 --> Drivers. Rebooted and the error "DRIVER_IRQL_NOT_LESS_OR_EQUAL(KBDCLASS.SYS)" went away. So, if you are running Webroot this may be your problem. Or if you have used Webroot in the past and have un-installed it , use Task Manager --> Details to see if wrkrn.sys is running. If so, follow the procedure that I used to get rid of it.

BTW, this problem didn't show up until I installed the Cumulative Update for Windows 10 Version 1511 for x64-based Systems (KB3147458). Getting rid of the Webroot wrkrn.sys did solve the problem, though.

Larry

[jak5 · Accepted solution]

FINALLY!!!!

I use webroot antivirus software, and have had good success with it so, removing it is not a great option. HOWEVER.... I, out of desparattion to see if ANYTHING will work -- I tried my partner's keyboard, Mouse (wireless) and logged in just fine!

NEW KWYBOARD/MOUSE solved the problem! (Guessing it forced the machine to re-load drivers)

Thanks for all of the input

JAK5

[HappyDayToYou]

LarryMeBoy posting spot on for me. My wife's PC started exhibiting this problem when I purchased a wireless keyboard and mouse last week. Strangely it did not fail immediately. Blue Screen maybe 4 times a day. Then it began to Blue Screen on the first key press which has made it easier to identify. She does not use Webroot but I found the webroot driver WRkrn.sys running when, encouraged by Larry's posting, I looked for it as suggested. It turns out my wife used Webroot 4 years ago.

I was unable to delete the WRkrn.sys file till I first edited the registry and rebooted without the file being loaded. Deleting the registry entry which was loading the driver was the key point. I also note what Larry said about the fact that it was only with a cumulative update releasd by Microsoft in April 2016 that this issue came to light.

[PaulMeln]

I had the same problem when I updated to the Win 10 Anniversary update - solution - swap out wireless keyboard/mouse from another PC ad restart system