This problem used to be present in LM 10, but was fixed in LM 11, not so in LMDE:
Right click on a folder or file and select 'Compress', then select '.tar.7z' as archive format and click 'Create'. Nothing happens except for a .<random_characters> (hidden) directory is created but no tar.7z archive. Other archives, even combined format ones, works fine. All the 7zip stuff is installed and I can create such an archive by first making the tar ball and the 7zip it, but it's very convenient to be able to do it from the context menu. The reason I use this archive format is that 7zip gives about 20% more compression than anything else I've tried but doesn't store permissions; tar takes care of that, so it had been great to get this problem fixed.