Unspecified Error

Hi

I think my file may be corrupted. I get the following:

Even though I've digitally signed the project so i don't have to enable macros each time, a security warning appears. When I click the stupid ribbon it has the standard Macros and ActiveX warning. It shows the digital signature is invalid and cannot be trusted. the macros will be disabled. I have no option to enable them.

When I click the Visual Basic button on the Developer tab, the following messages come up:
"An error occured while loading 'Sheet1'. Do you want to continue loading the project?"

If I click no, it says "The Visual Basic for Applications (VBA) macros int his workbook are corrupted and have been deleted. The macro corruption most likely exists in the current file. To recover the macros, open a backup copy of this file if you have one."

Then a message box:
"File not found"

If I then open the VBE, the macros are gone!

If I click yes, it goes to the VBE and all the macros appear to be there and look correct. However, I can't activate macros to run them.

Any suggestions on how to get the macros running again? Should I export the modules, save the workbook as an .xlsx, then re-open, import the modules, and save as an .xlsm?

What causes this kind of error, so I can avoid it in the future?

I should add that after a little investigation, I've found 'Sheet1' is a worksheet that I recently deleted out of the workbook. However, an icon appear for it under the VBA-Project Explorer.

Should I export the modules, save the workbook as an .xlsx, then re-open, import the modules, and save as an .xlsm?

Or just run AppsPro CodeCleaner, which does about the same thing.