Hi,
I have a problem which I can't get rid of, I don't find anything when filtering the preference window for "rar", so what do I have to do ?
When I doubleclick a .RAR file in DO, Winrar opens it (like I want), however when the rar archive has a numerical extension (like xxx.001, xxx.002 xxx.003 etc...), then DO opens the file internally.
Please, how can I stop DO from opening these files on its own ?
HOW TO: Make RAR files open in Opus on double-click
Maybe reading the above and doing the reverse will help you out. 
Your WinRar probably isn't associated with .001 and .r00 files so they fall through to the RAR VFS plugin, which handles .rar;.001;.r00 by default.
You can remove the extensions from the RAR VFS plugin's configuration but I doubt it's worth it (since the .rar extension is in the default config too but that is working fine); I think you just need to tell WinRar to associate itself with .001 and .r00 and things will work as desired.
Aah, Thanks a lot ! It's working now. 