Hi Markg2
You could try the following:
1. Clear the offending cell by right clicking on the cell and selecting clear contents.
or
2. Select the whole sheet with the exception of the offending cell, copy the data and move it to a new workbook completely.
Failing that, if it is not sensitive data could you post a copy and I can have a look at it for you or you could send it to my email and I will have a look (otpm@blueyonder.co.uk).
Hope that helps.
Tony