"The feature you are trying to use is on a network resource..."

The feature you are trying to use is on a network resource that is unavailable.

Click OK to try again, or enter an alternate path to a folder containing the installation package '(any program I try to install, update, or uninstall)' in the box below."

After clicking cancel, it gives me a different message depending on the program, but it always has something to do with not being able to uninstall the old version. I am also having trouble installing Windows Updates because it's showing the same updates every time I restart my computer, and some of the updates are failing. System restore fails when I try to restore my computer to when it actually worked. I have not used my computer since April and it was fine the last time I turned it off. I saw some similar threads but none of them were helpful to me. I am using Windows 7.

I hope someone can provide a solution. Thank you.

UPDATE: I used Microsoft Fix It to uninstall a certain program, and then I was able to install the new version. The problem seems to be primarily with uninstalling, if that helps at all. I was also able to install Firefox which wasn't already on my computer.