Update settings do not work.

I have a major problem with TV updating.

Currently I'm using TV v15.1.3937 but according to the 'update' button, it says there's an update v15.3.2682, but when I try to update, the progress bar gets as far as 1/2 way then quits, it does not install.

Is there an update file that I can manually download?  I have tried downloading the actual TV installation, but it wants me to completely remove any previous version instead of just updating it.