>>>Ok, I did find an active filter on that table that used THISFORM. A coworker suggested, because we can't change the filter expression right now, that I use the table with the AGAIN clause. Does this seem reasonable?
>>
>>FILTER expression should never use THISFORM in it. You need to set your filter expression though macro, e.g.
>>
>>lcFilter = "myField = " + thisform.SomeProp
>>
>>set filter to &lcFilter
>
>As I said, we cannot change it now. It exists, now I need to work around it.

Ok, try the following

lcFilter = SET("Filter")

set filter to

locate for myCondition and &lcFilter

set FILTER TO &lcFilter