Hello, I have this exact problem and it’s even worse cause when I try to delete the WeMod folder in Local, it’s saying it can’t be deleted because it’s running already, specifically squirrel is running itself ? I have no clue what to do as I don’t have an AV on and can’t even install anything.
Thank you.
End it via TaskManager first. Watch out tho since there is probably a not opened process of WeMod, just scroll a bit down, find and close EVERYTHING that is affiliated with WeMod. Should work then
Welcome to the community. 
First of all, please do not post in old threads that have been inactive for years. This is referred to as “necromancing” and is generally frowned upon in probably 99 out of 100 forum communities online.
I split your post into its own thread.
As the user above suggested, launch Task Manager. Locate all instances of WeMod under all the headers and right click them. Then choose “End Task”.
You have the default Windows Defender on your machine, which is an antivirus that cannot be removed because it is permanently embedded into the operating system.
Here are the instructions to resolving your installation issue, which is, 99% of the time we get this report, caused by a security program on your PC or network: I can’t Install WeMod / “There was a error installing the application” - WeMod App / Support.