What is this strange error message from Microsoft Office?

Q My PC runs Windows XP with Service Pack 3 and on this I use the 2007 editions of Microsoft Excel and Word 2007. In the last few days a strange error message has begun popping up, which reads: ‘Compile error in hidden module: ThisWorkbook’.

I’ve been using PCs for some years now, and have made sure my housekeeping is in order – so this computer should be in fine fettle. I can get rid of the message just by hitting Enter and the programs then run normally. Perhaps you have an idea of what’s wrong?
Mike Walsh

Read more: Microsoft Office articles | Reader questions and answers

A This error is caused by something that is attempting to launch at the same time as an Office application. Specifically, it is likely to be the result of an add-in that you may have installed to provide extra functionality in Excel (as implied by the ‘ThisWorkbook’ part of your specific error message).

Obviously we can’t guess what add-in this might be, but a process of trial and error should help you identify the culprit. To start, launch Excel, then click the Office button, point to Excel Options and click Add-Ins.

The Add-ins box will display a list of installed add-ins. If you recognise an entry as something you have installed recently note its type in the Type column and then select that same type from the Manage dropdown list below. Now click to remove the tick from the relevant box and click OK.

Restart Excel to see if this has cured the problem. If not, simply repeat until the offender is found. Then either leave the add-in disabled or – if it relates to a tool that you wish to continue using – download and install the latest version from the relevant developer’s website.