Automation Error - Catastrophic Failure EXCEL VBA

Question

I have a workbook which is throwing this error on opening. When it does and I open the VBA module, the current line is the definition of a sub. But the only option is to kil

Answer 1

Double-check your file extension. Excel spreadsheets with macros embedded need a *.xlsm extension, not *.xls.

Total 'for-dummies' answer, but I just made this mistake myself.

Answer 2

I had this message earlier today and it was due to another instance of Excel being open as a background process (the background process had previously opened the file in question, so it must have been something to do with that). Once I closed the other instance the problem disappeared.

It might be worth checking 'Task Manager' > 'Background processes' to see if that's the case.