Excel 2003 to 2007 & crazy processing times

[SueWithQuestion]

I have some very large spreadsheets that I was using with Excel 2003, and they contain primarily a formula that uses an = IF(COUNTIF...) formula that looks for the occurrence of values of interest from one worksheet in the file, being in another one of the sheets in the file.

Now that my company has (finally) moved from Excel 2003 to 2007, these formulas that did not cause any significant processing delay in 2003, are taking crazy long to process.

I have the Excel Options > Formulas > Workbook Calculation option set to Manual.

Does anyone have any ideas of what is going on here, or things I can try to reduce the processing time?

[DonkeyOte]

A standard COUNTIF function would be an unlikely cause of calc slowdown between versions - even if using entire column references.

To test: create a backup version of your file, remove the COUNTIF functions you mention and test calculation performance.
If calculation does improve I would ask you post back with one of the offending formulae - be sure to detail any named ranges in use etc (how they are defined etc...)