I have a workbook (format .xlsm) that used to work fine on my computer, but now something has happened. When I try to open the workbook, it briefly opens, and then Excel closes. I went to my local public library, and on one of their computers, the same workbook opens and runs just fine. Are there any general things to check when a workbook opens one day but not the next? I have not installed any new software on my computer. Thanks.

Try starting your file in Safe Mode (select the file, hold down CTRL key then press Enter) and once opened debug your macros to find when and what closes your file. If present start from the WorkBook_Open (or Auto_Open) macro.

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Thank you for your reply. I tried this but can't get it to work. The workbook briefly opens but the "busy circle" displays for several seconds and then Excel closes.

If you've successfully run Safe Mode, at this point, if it weren't for the fact that you said the file worked in a local public library PC, I'd say you have a corrupted file or that your Excel needs fixing.
Does this file contain sensitive data? how big is it ? can you attach it?

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Did you create the workbook on your own computer?

I thought at first maybe your security settings were high and it wasn't letting you run a macro-enabled workbook. But from memory, the message I got across the top was that the macros were blocked, so it wasn't that it wouldn't open the workbook.

Have you tried running the Repair tool on MS Office?

Thanks for the replies. I would prefer not to attach the workbook here. I tried the Repair tool, but that did not help. I have another xlsm format workbook that will open and run just fine on my computer.

Perhaps try saving it as xlsb on another computer and try running it on yours ?

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