Restart Steam solves, but this is happening everytime when I shutted down Empires and trying to boot again.
Yeah I got this just before while trying to run my oldpires and do some particling (can't use the editor in steampires dunnowhy) It's weird that it affects both steampires and oldpires. Mine resolved itself without a steam restart though.
try deleting clientregistry.blob (This works for almost every issue with steam ) also delete AppUpdateStats.blob But people say it is happening even after they delete it. Also try checking this: https://support.steampowered.com/kb_article.php?ref=2275-UFHC-2473 If you have any of those running in background. Also try deleting any cache folders in steam (appcache, depotcache or anything else that you find) Or you can try uninstalling and then reinstalling steam but keeping your steamapps folder. Also try restarting pc. Verifying Source SDKs. Are you participating in steam beta? If yes, turn it off....if not, try turning it on. Steam - settings - in beta participation click change - ... (I have hopes for this solution) Those are pretty much basic stuff to fix steam problems... But I have found no straight solution to your problem.
In there they have a link (programs that interfere with steam)that pretty much say this... "Have an anti-virus? Disable/Remove. Have a firewall? Disable/Remove. Have something that competes with our voice/chat service? Disable/Remove." Cuz its always a good idea to disable your AV/firewall for 3+ hours at a time right?
Yeah, ViroMan really does have a point here. So many times this is given as a lazy solution to problems, when it's really only the cause of it 1 in 100 times at best.
the AV is pretty much only usefull when downloading or installing something... But the point is that if you try that and get it working, you will know where is your problem
its a simple divide and conquer troubleshooting approach, its the users fault if they see it as solution (though ofc a short line remembering them wouldnt hurt anyone either)
But I have to say I had many problems that were caused by AV or FW but solution isnt disabling them. Solution is adding things to exceptions, because if you for example disable FW it will not disable all the rules that you have set. It will only disable notifications and stuff like that (atleast in comodo AV/FW)
The thing is, your Antiirus may hold exclusive use of some files when real time scanning is on and you have shit in your quarantine. Even files that seem unrelated to the shit in the quarantine. Just like when you want to use your webcam and the useless software that comes with the driver holds exclusive use of it and fucks shit up for the other software that want's to access the webcam via the driver.