Hi Chris
thank you so much for baring with me here

Folder C:\Program Files (x86)\Microsoft Games\Age of Empires II\SaveGame\Multi does not exist on my computer. Also I was not able to find any *.mgs and *.msx files including Multi.txt.

Here is the result of game diagnostics:

Non-DirectPlay game path is 'C:\Users\user\AppData\Roaming\Microsoft Games\Age of Empires ii'
Verifying 'C:\Users\user\AppData\Roaming\Microsoft Games\Age of Empires ii\language_x1.dll' exists...
Success!
Verifying 'C:\Users\user\AppData\Roaming\Microsoft Games\Age of Empires ii\age2_x1\age2_x1.exe' exists...
Success!
Voobly path is 'c:\program files (x86)\voobly'
Game version is '1.0C-VLY'
Verifying 'C:\Users\user\AppData\Roaming\Microsoft Games\Age of Empires ii\language_x1_p1.dll' exists...
Success!
Checking DirectPlay libraries...
Looking for dpwsockx.dll...
Looking for dplayx.dll...
'c:\windows\system32\dplayx.dll' size: 228352 bytes
DirectPlay Init Success!
Scanning installed DirectPlay games...
Age of Empires II - The Conquerors Expansion [found]
Game was found in DirectPlay registry!
DirectPlay play thinks the game is installed at 'C:\Users\user\AppData\Roaming\Microsoft Games\Age of Empires ii'
DirectPlay command line is 'Lobby SystemMemory'
DirectPlay play thinks the game exe is at 'C:\Users\user\AppData\Roaming\Microsoft Games\Age of Empires ii\AGE2_X1\age2_x1.exe'
Verifying file exists... Success!
DirectPlay play thinks the language dll is at 'C:\Users\user\AppData\Roaming\Microsoft Games\Age of Empires ii\language_x1.dll'
Verifying file exists... Success!
Scanning 'c:\program files (x86)\voobly\gamedata\AOC\age2_x1.exe'
Success!

Everything looks fine. DirectPlay is configured and the game was found on your harddrive. If you still have problems try rejoining the lobby or restarting your computer.

Your game installation must not be inside your home directory, this is an unsupported scenario. Please perform a clean installation as explained in this self-help article: [You must login to view link]

CD-ROM? I have the game on CD ROM, but I have no CD in my laptop.
I purchased all games on Steam and installed from there.

Before beginning of July (don't know Voobly version) the game was working perfectly and I haven't moved the installation folder

If you have the game on Steam, use this link: [You must login to view link]

Keep in mind, that you cannot have both installed. You either have AOK/AOC installed, or AoE II HD, but never both.