Removing .pdf from a file name

Trying to remove .pdf from the end of the file name. Using a formula text field I attempted to use the function Part([File],1,".") , but my file name will often have periods (different amounts) so I can't seem to get that to work, unless there is a way to use it I'm not thinking of.

I tried to use the function Left([File],".pdf"), but that still only looks at the period and not the entire string.

How can I remove the .pdf from a file name, where the file name includes periods?

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Mike Tamoush
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