At work I do a variance report each month by copying the workbook from the previous month, clearing the old data, and copying and pasting new data downloaded from our accounts database.
Having done that I copy and paste a couple of columns of data from the previous month into the new workbook.
Over the last couple of months the workbook freezes and comes up "not responding" when I do this. Could this be a user error ie. could I have accidentally copied some formulas or something that I'm not aware of? If so how do I find out how I screwed up? Is there some sort of error check formula I can use or one that put highlight all formulas in the worksheet or something.....?
I expect your report has a long editing history, so all sorts of junk may have ended up in your file. Copying and pasting information from one workbook into another is a process that causes all sorts of potential issues. For example, on the home tab, click to expand the Cell Styles Gallery while you have a fresh, new workbook window open. Now do the same with your reporting file open and compare the appearance. It is not unlikely that you have gained a lot of custom styles with funny names like Normal 1, Normal 1 1, Normal 1 2 1, ... Also, have a look at Name Manager (Formulas tab). Anything unexpected there? Finally (for this post anyway), on the home tab, click the binoculars and choose "Selection pane", check out how many objects are listed and whether that is expected. Make sure you select each worksheet to do this check.