|First of all, you say you are using Windows 7 but you are on the Vista forum.|
Which is it?
It is important to get the the fixes from the appropriate website.
This link is for Vista but they have a link on there for Windows 7 too:
I would try the LNK fix first and if necessary the EXE fix. Do NOT Run the file but Save it somewhere (desktop will do). You can either double click the downloaded file or right click it and select merge. You might have to right click the file and select "Run as Administrator". Finally, OK all the prompts. File association registry changes should take immediately. although there is nothing lost by restarting afterwards if you wish.
If either of these fix the problem then the next step is to check for viruses (likely cause). As a minimum run your AV, and also MalwareByes from here:
If possible fix the reported problem initially. as this could make any malware easier to remove.
Always pop back and let us know the outcome - thanks