I am told I have the wrong Settlers 3 version?

If you receive the following message, you will receive the following message when you start the aLobby:

The S3.exe does not match the expected version. Please install the patch for 1.60 and then replace the S3.exe with the XP-Patch.

Solution:

Install the patch for version 1.60. You can download it here: https://lobby.siedler3.net/download/s3old160.exe
Then download this file: https://lobby.siedler3.net/download/s3.exe - copy it into your Siedler 3 folder and replace the existing file with the new one.
Then restart the aLobby.