NSIS Error Writing Temporary File and other files not installing

[Everlong]

I was just clearing some stuff off my comp yesterday to make some space, and I found a "Downloads" folder in my "Favourites" folder. I thought it was just a shortcut, so I deleted it and then found it deleted everything in my actual downloads folder and I'd already emptied the recycle bin.

I did a System Restore and it got my downloads folder back and everything in it, but I think it's messed up some installer stuff. I downloaded the latest Second Life update and tried to install it and I get the error "NSIS Error writing temporary file. Make sure your temporary file is valid".

I only get the error with this version of Second Life though. I can install the previous version. Other errors include some "Windows Installer" errors saying "The Windows Installer service cannot be accessed", or some programs like Google Earth do nothing when I try to install them.

Some programs install, others give me these errors.

Tried searching and downloading and reinstalling Windows Installer 4.5 and did the misexec.exe /unregister thing in cmd that's on the Microsoft website, but still nothing.

 

[Flavius]

Check you have folders C:\Windows\Temp and C:\Users\<your account>\AppData\Local\Temp.Check also you have correct declared variables in Environment Variables (Control Panel>>System>>Advanced System Settings)



(I have different settings than original becaused I moved C:\Windows\Temp a while ago)

 

[Everlong]

All the temp folders appear to be there.

It seems to be something with the Windows Management Instrumentation files. When I right click on My Computer, CPU and RAM have "not available" next to them, and when I try to load System Information, it says "Cannot access the Windows Management Instrumentation files. Windows Management files may be moved or missing".

I guess I'll try a system repair or something.

 

[Everlong]

Ended up just re-installing Windows.

Couldn't do a repair install as the "upgrade" option was greyed out as it was going on about can't use 32 bit to upgrade 64 bit, which is kind of a catch 22.

Did the sfc /scannow and that fixed some errors, but didn't fix the problem.

Came on this morning and it wouldn't play music of video files, so just backed everything up and installed Vista again.

No idea why all this happened just becuase of a System Restore, which was successful