Frank Kabel wrote...
have you tried the UDF?. It should return only this version
number. At least it worked for your example data?
..

*YOU* didn't test your UDF on the filenames

Ack, got me :-)

[....]
Anyway, a UDF that copes with all the OP's variations given so far
needs to locate the rightmost numeric substring, and that requires at
least two loops - first to find the end of the rightmost numeric
substring, then to find it's beginning. Here's an alternative UDF
that's more permissive with its argument and returns a string rather
than a number, so strings without such numeric substrings return ""
rather than #VALUE!.

like your approach. And your UDF also covers 5_5 (what my seond UDF
does not)


Frank