Everyone's already said wrong section so;
You will need to perform a full re-installation of Project Blackout as well as disable some programs which may conflict with Project Blackout;
To perform a full re-installation you must uninstall the program as normal, search for any "left over" Files, and run a cleaning program such as;
CCleaner - Optimization and Cleaning - Free Download
To delete any temporary files or miscellaneous files the game may have had.
At this point you may want to restart your computer.
Now, before you re-install you will need to disable your Anti-Virus Program / Firewall (This is temporary), You may want to go so far as to disable all unneeded programs prior to re-installation to be safe, as some can effect certain game files, You can do this task manually or of course by using;
SmartClose download and reviews from SnapFiles
Now you have a clean slate, Re-install Project Blackout from a source that you trust here;
Project Blackout ? The Online FPS Battlefield
When installation in complete and if everything works properly simply remember to add Project Blackout to your Anti Virus Program's "exceptions list" if there is one, so you can protect your computer once again.
Hope it helps, barley trying my hand at Project Blackout myself.