Messed Up Mouse PS/2 Drivers

[Daiken]

Background, I'm somewhat of a techie, not much. Been playing around with Windows 7 recently, 64 bit. Just need some help/advice.

I have an old Logitech MX510 mouse and I wanted to install the Logitech software so I could program the buttons. Turns out Logitech doesn't offer anything past XP. So I downloaded the XP versionof the software and ran it on my Windows 7 in compatibility mode for XP (SP2), as administrator. Everything installed, but the mouse software didn't work. Windows driver was overriding Logitech, probably because it was more recent.

So I tried uninstalling the logitech stuff seeing as it didn't work. Unfortunately I got an error saying I was missing a file i8042prt.sys and therefore the software could not be uninstalled. Hm, I looked up the file and supposedly it should be in Windows/System32/Drivers. I didn't have it, so I thought I'd be smart. I copied the file from my old Windows XP directories and pasted it into the correct location, ran the uninstall, and everything was removed easily. Cool, so after that was done I thought that well I shouldn't leave a random file around in my systems folder so I tried deleting it.

Turns out, I couldn't delete the file I had pasted (i8042prt.sys) because I no longer had permission. As administrator this was kinda weird so I looked at who had permission. Only System and TrustedInstaller (I'm guessing this came from the Logitech software installer) had full permission. As admin, I could only read and execute. Looked around at some of the other files I have in my Drivers folder and the permissions were all similar. Administrator didn't have permission for most of the files, but TrustedInstaller did.

So...anyone know if this is a problem or anything? Everything seems to be working fine...but it kinda irks me that even as admin I can't touch many files. On a side note, I'm curious to know if the i8042prt.sys file was there originally and got deleted or if it's only there because I put it there. I would appreciate if anyone running Windows 7 could check and lemme know. Thanks!

Edit: Also this is still a pretty fresh install, so no system restore points before the incident...

 

[Daiken]

Ah, I kinda figured it out looking at other people's posts. I learned how to take control of the files. Removed TrustedInstaller from the list, gave it to administrator and my account. Then I went ahead and deleted the file i8042prt.sys. Everything still works fine so I think I'm good...

 

[Daiken]

Blah, okay. I deleted the file and ran into other issues. I'm using PS/2 port for my keyboard so after removing the file and restarting, my keyboard stopped working. So I put the file back...all I want to know now is whether or not the file is supposed to be there or not? Can anyone please just check and lemme know if they have it?

 

[thefabe]

Blah, okay. I deleted the file and ran into other issues. I'm using PS/2 port for my keyboard so after removing the file and restarting, my keyboard stopped working. So I put the file back...all I want to know now is whether or not the file is supposed to be there or not? Can anyone please just check and lemme know if they have it?

Here is some information on your file you deleted
i8042prt.sys Windows process - What is it?

 

[Daiken]

Thanks. I've seen the link already. I just want to know if the file was there for people using Windows 7, because when I tried installing the software it couldn't find that one file.