Calculation failure in 1 file but not another

[cfor]

I have 2 files with the same calculation field in both files.

It works in 1 file but not the other. I have no idea why. Any insight?

The table relation is the same in both files - tableA relates to tableB thru recID = recID_tableA

other fields populate fine.

TableA field is a calculation field

if(tableB::mark = "yes"; tableB::num; "nop")

In the first file, the calculation returns tableB::num.

In the 2nd file, it returns "nop" when it should return tableB::num.

I'm stumped. I've deleted the field and recreated it, I've tried different options that should deliver the same result. The end result is the same - it works in the 1st file but not in the 2nd.

I've tried using the recovery command but everything comes up as fine.

Do you think it could be some kind of corruption?

thanks

[comment]

Why don't you post a copy of the file showing the problem.

[cfor]

Unfortunately, the file is work related and I'm not able to post it.

[Lee Smith]

We do not need to see your data, so you could do a "Save a Copy As, Type clone (no records), and post that instead.

Or, if you can recreate the problem in a set of files, you can post that instead.

Lee

[comment]

We do not need to see your data

Actually we do, because the prime suspect here is that tableB::mark does NOT in fact equal "yes". But all other fields that do not play a part in this can be deleted.