I have completed the steps in that particular thread asked. Checked the antivirus for malwares and rootkits, used the Win7 fixing tool, as well as getting SFC /scannow to see if any of the .dll files are damaged.
The multiplayer is capable of running with BattlEye uninstalled, but I'll get kicked out due to anti-cheat.
I assume my computer is just old and have decided to install Windows 10 and see if it'll solve the problem, then.