You need to tell us about what it is you are uninstalling or installing? What addons are you using? Version of Kodi?
If you don't understand the log, post it so those who can read it can troubleshoot it.
See my signature on how to post an error log.
The TVADDON addon "USTVnow" does not work. The error message that flashes momentarily at top of screen says something like "invalid credentials"
I tried to upload log per instruction, but could not read the flashed error message, but think it was something like invalid url. The message is extremely fast, so that even after several attempts I cannot read why the log cannot be uploaded.
hey I'm no geek I just try and follow instructions from those that are!
"invalid credentials" means either you don't have an account or you've tried to login with incorrect details.
also you'll have to either be in the US or use a VPN US server.
hope this helps.