I can open the all my workbooks. They are not corrupted.
I can open them from the recently used list or go to open file.
When click on a Excel shortcut Excel will open but the workbook will not.
UNRegserver/REGserver appears to do nothing when Excel.exe is started from the "run" box.
Microsoft Excel topics include formulas, formatting, VBA macros and user-defined functions, and everything else related to the spreadsheet user interface, including error messages.
Check this:
Excel
File
Options
Advanced
General Section
Ignore other applications that use DDE
Make sure that setting (Ignore other applications that use DDE) is OFF.
Thanks,
Alan.