I started getting this error after updating to the latest version (25.8.5). The path is G:\Programs\PortableApps\LibreOfficePortablePrevious, and the file exists. If I delete the LibreOfficePortablePrevious folder, and replace it with the pre-update version, it works.
"LibreOffice Previous" can be opened, but not "LibreOffice Calc Previous" or "LibreOffice Writer Previous", etc.
It's working here without an issue. Any chance it was still running or something or any files were locked as you upgraded? What OS are you using?
Sometimes, the impossible can become possible, if you're awesome!
I've tried it multiple times across 1-2 weeks. Win 10 x64. No files should be locked or in use.