I have a file (CCS9.1) from a trusted source (TI.com)that was put in Quarantine and I cannot change it with XATTR. CCS 10.0 from TI.com will open. What can I do?

The first random file that I checked for a quarantine bit on my macOS 11.2.3 Desktop was a PDF.

xattr -d com.apple.quarantine ./tb.pdf

That syntax whacked the quarantine bit on the first try. The -r recursive switch in the previous linked example would not work on a single file, but would on a folder of said files. Notice I didn't need sudo either.

Try it again without the xattr recursive flag.

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Does this help in clearing that Apple quarantine bit on the file?