@mysterysimmerr
I would add a little bit to what Crin said. The UAC setting is right, but you can try it as follows:
1. First uninstall Origin from your computer
2. Change the UAC settings to Always notify as per link that Crin provided - http://windows.microsoft.com/en-us/windows7/how-do-i-change-the-behavior-of-user-account-control-by-using-the-slider
3. Once the UAC is changed, download and install Origin and confirm all pop up windows that may show up
4. Once Origin installed, try to log in and install your games again, all should be fine now
Hope this helps 🙂
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