Worksheets slow to close

[belleflex]

Excel 2010 - worksheets are taking 15-20 seconds to close . Any ideas as to why this started to happen a few days ago ??
Thanks

[2Excel]

Does it say they are processing in the lower right?

[belleflex]

No it does not.

[Vibu212]

There is a possibility that the file is too big. A file can be too big if a random cell outside of your data range has any input/formatting applied to it. You can clear formatting outside of your data range using the guide here

http://support.microsoft.com/kb/244435

[belleflex]

File size doesn't matter. It happens even if I open a new worksheet and don't enter anything.