MTA:SA fix

There was a problem validating your serial

MTA could not confirm the serial that identifies your computer. Update MTA first. Inside a virtual machine, or on Linux, Steam Deck or a Mac, MTA has one extra step for each.

Steps

Try one step, then check whether the problem is still there. Follow any "only if" line before changing a setting.

1. Install the current MTA

   The MTA FAQ says an "Invalid serial number" error means your MTA is out of date. Download the latest version from the official site and install it.

2. Windows inside a virtual machine

   Only if you run MTA inside a virtual machine.

   Install and run MTA once on the real computer, outside any virtual machine. Then try MTA inside the virtual machine again.

3. Linux or Steam Deck

   Only on Linux or a Steam Deck.

   Install and run MTA's Linux server once on the machine itself, as root and outside Wine or any virtual machine. Then start the MTA client again. On a computer with only NVMe drives, the Linux manual adds that a SATA or USB drive must be connected while you do this.

4. Mac

   Only on a Mac.

   Download and run the small tool that MTA's serial validation page links, on the Mac itself. If macOS refuses to open it, allow it under Security & Privacy with Open Anyway. Then try MTA again.

5. Cloud gaming or a rented cloud PC

   Only if you play through a cloud gaming or cloud PC service.

   In December 2020 the MTA team announced that serial verification also covers cloud gaming platforms and cloud virtual machines. The fix needs access to the real machine that hosts the virtual one. Those services do not give you that, so MTA says most cloud gaming users can no longer play. If you control the host machine yourself, the virtual machine step above still works.

6. If you ran a serial changer or spoofer

   Only if such software was ever run on this computer.

   MTA's page says this problem on Windows can be caused by serial changing or hardware spoofing software. MTA does not help undo that and advises reinstalling Windows completely, because such software may also have put malware on the computer.

   Careful: Programs that promise to change your serial come from unknown sources. MTA warns that the computer may be watched or part of a botnet afterwards.

Other problems like this

• MTA will not start in a virtual machine or sandbox
• MTA says Windows is in Safe Mode
• MTA says it is incompatible with software on your PC
• MTA warns that it could not detect an anti-virus
• CL29: client integrity warning at launch
• Another MTA or GTA instance is already running
• MTA data files or core.dll are missing
• MSVCR, VCRUNTIME or core.dll cannot load

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