Remove the last x characters in a certain condition

[Hughso2]

Hello all,

I have a set of 2000 Pdf files that are named Fname Lname_Certificate-num_DOB_counter.PDF In some cases there is an extra _ Counter.pdf. I would like to remove the second _Counter it is consistently the 4th underscore. I am thinking that a regex might work but looking for some ideas.

Thank you in advance
Ian

[Hughso2]

Al;
Sorry I figured it out. It was more straightforward than I had originally thought.

I used the replace *_*_*_*_* with *_*_*_*

Thank you
Ian

[Admin]

Hi Ian,

yes, that's it, and you could also do it this way:

Use Simple mode with a match that captures the name segments around the 4th underscore and a replace that drops that 4th segment.

Example (turn on RegEx (1) -> Simple):

- Match: %1_%2_%3_%4_%5
- Replace: %1_%2_%3_%5

What this does
- %1 = everything up to the 1st underscore
- %2 = between 1st and 2nd underscore
- %3 = between 2nd and 3rd underscore
- %4 = the 4th segment you want to remove
- %5 = the rest (after the 4th underscore)
- Replace reassembles the name without the 4th segment (and without its underscore)

Notes and tips
- This works on the filename (not extension) — leave Inc. Ext. off unless you intentionally want to include the extension.
- If some files already lack a 5th segment, they will not match this pattern; test first on a selection.
- Test on a small subset and/or make a copy/backup before renaming 2,000 files.
- If you want to run a no-op for files that don’t have a 5th segment, you can preview selection and only apply to files that change, or use the multiple-RegEx editor to add additional rules if needed.

It is similar to the replace option.