Solution - Device Installer Error

I kept on getting error messages at startup reading "Device Installer Error: Windows could not load installer for Keyboard. Contact your hardware vendor for assistance." Then I would get a screen to search for a driver but no amount of searching ever found anything that worked. I would get the same message for "mouse" and for "volume" and sometimes for "hdc". I could click past the message and the computer worked fine. No noticeable problems. I lived with this for 6 months, trying various solutions to no avail. Following someone's advice to solve a slightly different issue, I went into the Windows\System32 folder and marked "syssetup.dll" as "syssetup-old.dll" and then expanded a copy of the file from the I386 folder. Complete solution. Obviously the old file was corrupt.
If you don't know how to expand the file, you will find the I386 folder in your Windows directory, such as "C:/Windows/i386". The file is probably shown as "syssetup.dl_" meaning it is compressed. If you hit Start, Run, and type in "CMD" to get the DOS prompt, just type in
expand C:\Windows\i386\syssetup.dl_ C:\Windows\system32\syssetup.dll
Then reboot.
In the above, just ignore my quotation marks when they appear. Just type in what is between the quotes.
I hope this helps you. It worked like a charm for me.