What's new

Win 7 to Win 10: apc_index_mismatch (portcls.sys) BSOD


**This issue is for my laptop which was originally running Windows 7 Home Premium**

I am getting huge amounts of error messages when updating from Win 7 Home to Win 10 Home (standard upgrade), clean install of Win 10 Home, reformatting the HDD completely, etc. I literally tried at least 10 times with varying degrees of success.

The computer seems to work fine in Safe Mode (with Networking). One time, it worked fine to the normal desktop and I even got sound for the first time, but when I install Windows Updates and restart, when it is configuring them, it automatically restarts and then I get the ":(" message and sometimes it just has

apc_index_mismatch (portcls.sys)

The error messages lately have been appearing on system boot, and if the system manages to start into the normal desktop, it'll BSOD after 15-20min even on idle.

My laptop is a Pentium Dual Core T4300 (2.1GHz), 4GB DDR2 RAM, 250GB HDD, Mobile Intel GMA 4500MHD graphics, and Realtek HD Audio. I've been having a hard time getting audio to work, but the last time it was audible was when I rebooted the system and it crashes on system boot everytime now.

What log files should I upload here? It's getting quite frustrating. I'm not sure if it's just being an older laptop (from about early 2010) and the drivers for Windows 10 not being fully compatible. When it gets to the desktop, it's just as fast as my Surface Pro 3 in many ways.

Thanks for the ramble and I hope I find a solution!