So I have run out of ideas on what to try for a problem I am having for a user in my office, and I was hoping a few people here may have seen this. The problem is when she opens a .xls file on a shared directory it always opens in read-only mode, even though it prompts her to choose "Read-Only" or "Edit". It will not allow her to save any changes back to the file.

1)She is using Office 2007, so the files are also opening in compatibility mode as well as Read-Only.
2).xlsx files as well as .doc and .docm open just fine.
3)She can go to any other PC and it works just fine so it's not her permission to the folder
4)In Control Panel-->Folder Options "Open" is the default action for .xls, and Microsoft Excel is the default program.
5)We use a sharepoint page to manage the files, she is clicking a link there to open the document.
6)None of the files are flagged as read-only, and it is all the .xls files in there.
7)Opening a .xls file locally on her PC works fine.
8)Not just her windows profile, because I have the same problem on that PC. Works just fine on other PCs.
9)Tried both repair/reinstall of office, even tried going back to 2003.
10)Read-Only recommended is not checked in general options.

Anybody have any experience with an issue like this or any other ideas I could try?
**Update** Also she is on .net 4 if that helps