Clearing the cache can fix a log of issues, especially on shared computers, but If you are still having trouble opening Office docs (in particular Excel sheets linked to other sheets and data sources) here are a few ways that may help fix it.

NB. It is worth testing your issue on another PC first as this article assumes the issue is isolated to a single computer.

1. Log Out of the Office:

• Go to your SharePoint site and log out in the top right hand corner
• Close all your browser sessions
• Go back to SharePoint and ensure you are logged out (you will be prompted to log in)
• Now open Excel on your desktop and in the top right, click sign out:

• Now return to SharePoint and you will be prompted firstly to log into SharePoint, then into Office

If this has not fixed your issue try doing a Repair...

2. Repairing Office

Note, this may require admin access to the PC.

• Click start in Windows and type "Programs" and select Add Remove Programs

• Scroll through the installed programs until you reach Microsoft Office

• After clicking Modify, choose the type of repair and let it run its course

After a restart, Office should be updated and you can retest opening the document