Reference not valid error - cannot find any invalid references

[bg56]

I have a somewhat complex spreadsheet that has recently started giving "Reference is not valid" error every time I hit "Refresh" or "Refresh All" (Data). I only have two pivot tables and have confirmed neither refers to a data source outside the current workbook. I have also reselected the source and get no errors when doing so (options/change data source). The interesting thing is that no matter what page I am on, if I select Data/Refresh, I get the "Reference is not valid" error. It appears my pivot table refresh is actually working, I just have this error everytime.

Any suggestions or ideas on how I can find the offending problem and correct this?

Thanks

 

[oldbrewer]

make a copy of the spreadsheet and start deleting chunks of it, testing to see if error still present, say chunk 5 solves the problem, make another copy and delete only chunk 5, if problem goes away make another copy and break chunk 5 into smaller chunks...........

 

[bg56]

make a copy of the spreadsheet and start deleting chunks of it, testing to see if error still present, say chunk 5 solves the problem, make another copy and delete only chunk 5, if problem goes away make another copy and break chunk 5 into smaller chunks...........

oldbrewer - thanks... I actually had begun that process but was hoping for something more efficient. I never figured out the exact cause but had enough backups to reassemble a working sheet after a few hours of work.
Thanks again