FATAL ERROR: Failed to connect with local Steam Client process

[Myuri]

So.. I'm getting this error now upon starting CS:GO. Besides this, I can't even start any other game from steam. It says "Preparing to launch..", then it closes, and it opens again and again.
Ive spend the last 8 hours to figure out what the heck is wrong with steam, tried everything i found and nothing helped.

Things I've tried:
-Restarting Steam
-Restarting PC
-Repairing the steam service
-Check games for missing files
-re-installing steam
-re-installing windows
-Installing steam on different drive
-Installing steam in windows safe mode

Never had this error before. I already contacted the steam support but i guess i will wait a long time for an answer. Does anyone know how to fix this?

PC specs:

Operating System: Windows 10, latest updates
CPU: I7 7700k
GPU: GTX 1070
RAM: 16GB G.Skill Trident Z RGB DDR4-3200
Motherboard: MSI Z270 Gaming Pro Carbon

(Sry for spelling mistakes, I'm very tired right now.)

[univega11]

I hAVE THE SAME PROBLEM! steam should fix this quickly!!!!

[BOT]

https://www.youtube.com/watch?v=NsGhodK-2ds