Teamviewer windows 7 only works in safe mode

After the newest update i can only get teamviewer 14 to work in safe mode. Have full admin rights. keeps coming up with Windows cannot access the speicifed device,path or file. You may not have the appropriate permissions to access the item. 

When i have tried to reinstall at the end of the installation a box appears saying teamviwer cant run but will continue the installation. the shortcut does not have the teamviewer icon, unless its in safe mode. 

Teamviewer technical claim i have a virus or corrupted windows. I have neither as run virus, registry cleaners, checked windows and its runing perfectly fine. 

Any help as ive just bought a subscription for the MD and now it wont work on his laptop.