Hey guys just updated DCS 1.5 beta to latest patch and had no idea about potential conflict with Mig 21.Do not update DCS 1.5 beta untill you have deactivated mig 21.Or just wait untill they put out another patch
See here https://forums.eagle.ru/showthread.php?t=185397
There was a post about having to deactivate the Mig 21 before patching but I missed it and I think I may not be the only one!
Official announcement https://forums.eagle.ru/showthread.php?t=185325