THEN has no corresponding IF or WHEN clause

Synopsis
This is an error in the way the REXX script is written. Some THEN keyword appears where it should not be.

Cause
You forgot to put an IF or a WHEN keyword before the THEN keyword.

Cure
THEN can't be used without a preceding IF or WHEN. Make sure that, for every THEN, there is one matching IF or WHEN before it (and no other THEN inbetween).

Cause
You tried to name a variable then in a place where a THEN keyword would be illegal.

Cure
In certain instructions, you cannot use the (unquoted) REXX keyword THEN for a variable name.