I've used a few hours now trying to sign files that are locked.
Can't depbo them to use addon builder and sign them, normally I use DSUtils and sign the files but I got only errors on files that were locked, basically, I'm getting:
Files C:\...\arma3...\filesname.pbo are not signed by a key accepted by this server. To play on this server, remove listed files or install additional accepted keys.

Even doe it's signed and the key is added into the key folder, tried creating a new key, tried having the creator give me a signed version of what he had but still no luck, he had it working on the non-dev branch but it does not seem to work on the dev branch.

This can be a very big issue for the modded servers.