Afternoon all (Morning for some of you)

I have a table which has a corrupt index expression
Ie there is an index in the table which points to a field which does not exist

Each time I open the table it gives an error "Variable 'OD_CD' is not found." (In fact it should be prod_cd)

It's easy enough to fix this issue.. I could just do a delete tag all & recreate (or similar)

But I was wondering how do I detect this kind of issue programatically?
If I do something like the following:

llFlag = .f.
On error llFlag = .t.
Use table in 0

If llFlag
  Wait Window 'Error occurred'
EndIf

the flag is not set correctly & a VFP error still comes up, which I don't want my users to see.

Does anyone know of a way to either trap for this kind of error or detect the issue in the dbf? (I can see a million suggestions for SDT coming in my direction)

TIA

Will