I ran the launcher today and it received an update of 3.5 MBs The "remembered" login info was cleared after the update. Works fine for me was able to connect to Multiplayer via the launcher.

Post logs if you want to get answer.

Hello people!
YO!
GalaxyClient doesn't work anymore!!! And the game launches only if I run it directly (AvP_classic.exe).
It used to work on my previous user account, but it does't even start on this new one.
I have uninstalled it and reinstalled (it's this well written?) many times, and on diferent drives (On C: and my games drive D:).
The first time it launches, does a quick update, and then nothing.
I'll reinstalled right now to see if the problem perssist... yeah, same outcome, no error messages, no windows, no nothing... just the 3.5 update and nothing, silence, agony and hope.
My guess is that there are some remaining files or reg files form my previous user profile. It has to be since the installer detect the last installed location (drive D: in this case).

SCRATCH EVERTHING!

Found the problem AND the solution (I'm so awesome)
The uninstaller doesn't delete the folder "C:\ProgramData\GalaxyClient".
That was causing the problem.
Uninstalling + Deleting Folder + Reinstalling = Working again.
I hope this become useful for somebody.
Cheers!

The launcher has failed to start, every time I've attempted it. Just a desaturated launcher screen, then it generates a crash report. Oddly enough, it seems to update, fine.

Ran the launcher today and it downloaded 3.6 MBs. Was able to join a Mulltiplayer game immediately afterwards.

Everything worked perfectly fine but the launcher downloaded ~120 MB after the first launch, I think (apparently a different download size than in case of other users for some reason). Multiplayer worked like a charm.

Launcher was smooth as silk on my system. No issues at all to report.

launcher installed with no problems, downloaded AvP, again with no problems, the game launched and ran fine in both sp and mp and i came straight to the forum using the option to send feedback through the client.

For me once every few days GOG Launcher is updating itself. It downloads 3.6MB package, updating successfully but version stays the same: 0.1.0.456. After checking logs it looks like version is ok, but updater found file with wrong hash. GOG Launcher is not asking for Administrator privileges.

Also I want to suggest, that proper information for user should be shown if such situation occured rather than "updating".

My system is Win 8.1 x64.

Logs:
2014-12-13 11:16:21 [galaxy_updater][Information]: Remote version: 0.1.0.456, current version: 0.1.0.456
2014-12-13 11:16:21 [galaxy_updater][Information]: Galaxy Client does not need to be updated at this time.
2014-12-13 11:16:21 [galaxy_updater][Information]: Parsed metadata of 2 files
2014-12-13 11:16:21 [galaxy_updater][Information]: File hash mismatch: C:\Program Files (x86)\GalaxyClient\GalaxyPeer.dll. Download attempt 1.
2014-12-13 11:16:21 [galaxy_updater][Information]: File C:\ProgramData\GalaxyClient\downloads\GalaxyClient\GalaxyPeer.dll doesn't exist
2014-12-13 11:16:21 [galaxy_updater][Information]: File hash mismatch: C:\Program Files (x86)\GalaxyClient\GalaxyPeer64.dll. Download attempt 1.
2014-12-13 11:16:21 [galaxy_updater][Information]: File C:\ProgramData\GalaxyClient\downloads\GalaxyClient\GalaxyPeer64.dll doesn't exist
2014-12-13 11:16:21 [galaxy_updater][Information]: File GalaxyCore/24592195/windows/GalaxyPeer.dll.zip starting download...
2014-12-13 11:16:21 [galaxy_updater][Information]: File GalaxyCore/24592195/windows/GalaxyPeer.dll.zip downloaded...
2014-12-13 11:16:23 [galaxy_updater][Information]: File hash mismatch: C:\Program Files (x86)\GalaxyClient\GalaxyPeer.dll. Download attempt 1.
2014-12-13 11:16:23 [galaxy_updater][Information]: File up to date: C:\ProgramData\GalaxyClient\downloads\GalaxyClient\GalaxyPeer.dll
2014-12-13 11:16:23 [galaxy_updater][Information]: File GalaxyCore/24592195/windows/GalaxyPeer.dll.zip downloaded and verified
2014-12-13 11:16:23 [galaxy_updater][Information]: File GalaxyCore/24592195/windows/GalaxyPeer64.dll.zip starting download...
2014-12-13 11:16:23 [galaxy_updater][Information]: File GalaxyCore/24592195/windows/GalaxyPeer64.dll.zip downloaded...
2014-12-13 11:16:25 [galaxy_updater][Information]: File hash mismatch: C:\Program Files (x86)\GalaxyClient\GalaxyPeer64.dll. Download attempt 1.
2014-12-13 11:16:25 [galaxy_updater][Information]: File up to date: C:\ProgramData\GalaxyClient\downloads\GalaxyClient\GalaxyPeer64.dll
2014-12-13 11:16:25 [galaxy_updater][Information]: File GalaxyCore/24592195/windows/GalaxyPeer64.dll.zip downloaded and verified
2014-12-13 11:16:25 [galaxy_updater][Information]: Locking files...
2014-12-13 11:16:25 [galaxy_updater][Information]: Locking files, before move...
2014-12-13 11:16:26 [galaxy_updater][Information]: Moving C:\ProgramData\GalaxyClient\downloads\GalaxyClient/GalaxyPeer.dll to C:\Program Files (x86)\GalaxyClient/GalaxyPeer.dll
2014-12-13 11:16:26 [galaxy_updater][Information]: Moving C:\ProgramData\GalaxyClient\downloads\GalaxyClient/GalaxyPeer64.dll to C:\Program Files (x86)\GalaxyClient/GalaxyPeer64.dll
2014-12-13 11:16:26 [galaxy_updater][Error]: File Access Denied Exception when trying to remove directory: Access to file denied (C:\ProgramData\GalaxyClient\downloads\GalaxyClient)
2014-12-13 11:16:26 [galaxy_updater][Information]: Update complete, total 2 files updated
2014-12-13 11:16:26 [galaxy_updater][Information]: Releasing Updater process mutex
2014-12-13 11:16:26 [galaxy_updater][Information]: GalaxyUpdater exited with return code 0: Returned successfully.

For more then a week I am not able to play multiplayer mode. The game always informed me that no session was found. Do I have a technical problem or there are no other players?

Just no other players i think.
I had the same message a few times.
I was was able to host and a few other players jumped in only for a short time then quit the hosted game.
Also i was able to join a session.
Not sure if this helps.

Launcher installed and updated AVP without any problems.
Also did all the updates without any issues.


------------------
System Information
------------------
Time of this report: 12/23/2014, 23:17:14
Machine name: GG-PC
Operating System: Windows Vista™ Home Premium (6.0, Build 6002) Service Pack 2 (6002.vistasp2_gdr.130707-1535)
Language: English (Regional Setting: English)
System Manufacturer: MICRO-STAR INTERNATIONAL CO.,LTD
System Model: MS-7345
BIOS: Default System BIOS
Processor: Intel(R) Core(TM)2 Duo CPU E6750 @ 2.66GHz (2 CPUs), ~2.7GHz
Memory: 3070MB RAM
Page File: 2220MB used, 4135MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
DxDiag Version: 7.00.6002.18107 32bit Unicode

Wrong area

Launcher worked fine during stress test
Updated with no problems

Flawless game launch, after a 120Mb update download. Started a multiplayer AvP game and joined one of the available hosts. Everything worked well, no issues at all. Reporting back with feedback through the link provided in the client.