Cannot access the Ribbon functions in Excel 2007 or Word 2007

[NELVON]

I have Office 2007 on Windows 7.

When I am working on a sheet (or document) the ribbon can become inaccessible, nothing works when I click it (like a 'Not Responding' screen).

If, I switch to another open sheet/doc and then switch back the ribbon is accessible again!

I have uninstalled/reinstalled Office plus SP's twice but the problem persists, and, as is usually the case, this does not happen all the time but enough times for it to be really annoying!

Any ideas?

Thanks for your time on this

Neil

 

[Neutron16]

Could you please post a screenshot or two?
And what are file sizes (MB)?