Software Cache & Update Error

[MysteriousVampire]

Hi, I started receiving error while checking my Laptop for updates. When I opened Software Update, and checked for any recent updates, I started getting this message-

Then, I thought that changing Update Server would fix the problem so I headed to change the Server and after changing server, when I clicked on Refresh Cache, I started getting another error-

Please help me to fix this problem.
Thank you.

[FrenchPress]

It looks like you are having a problem with manually added PPA.
Untick
stacer
from the list of repository (in Software and update) and try update again.
Mine looks like this:

[Kedric]

You added a ppa manually, I think u can remove it. Isn't stacer in the ZorinOs repositories?

[FrenchPress]

@Kedric

Isn't stacer in the ZorinOs repositories?

Indeed.
I just checked. it is in Software, no need to add it manually.

[MysteriousVampire]

Should I uninstall Stacer and then again Install it from Software Center?

[FrenchPress]

@MysteriousVampire

Should I uninstall Stacer and then again Install it from Software Center?

I think you should.