How to Repair Microsoft Excel

What to do if add-ins do not run

If you are getting error messages like “error in module 1”, “unspecified error”, or “undefined reference”, the problem is not with our add-ins! It is a problem with the installation of Office. Random Excel crashes, especially when Excel is closing, are also an indication of a bad installation of Office.

  • We have tracked some crashes of Excel to having kept old versions of Excel installed. Do the repair on all releases of Office you have, even if you are not using a particular release and just kept it installed.
  • Another cause we have found for random crashes is partially corrupt workbooks. How do they get corrupt? More ways than one to count. One we have noticed is corrupt workbooks made outside of Excel. Sometimes they work fine. Sometimes they don’t. The solution in this case is to realize it is workbook-dependent. Then, the solution is to create new workbooks. And doing copying of sheets to a new workbook is not the solution. Do copy and paste special values and recreate formulas and graphs.
  • The number one cause is still a bad or corrupt installation of Office, which a repair may solve.

    • The simplest way to repair Office is to:

    • Reboot First
    • Go to Add or Remove Programs.
    • Right-click on your version of Office or Excel and do a repair.

    If this fails, then first completely uninstall office per these Microsoft instructions then re-install. Make certain you have your Microsoft ID and you re-download the latest version of Office or Excel before uninstalling.

    If the message you are getting is an out-of-memory error or not enough resources, then most likely you have too many COM  (Not VBA/Excel add-ins) installed.   See memory problems for how to fix. More than two COM add-ins can cause such errors.