"incorrect et.exe"

You get this error when you are trying to connect to a server that is running another patch. You have patch 2.60 installed by your ET. When you see this error you know that the server is running on version 2.60b
To connect to the server you only have to install this patch. It's not like the 2.60 patch because this is only a small upgrade. You will have to replace 2 files. These files you will find in the .zip file below (you can download it with the link). The files you'll need to replace are "ET.exe" and "ETDED.exe".
You can find these files in the folder: C:Program FilesWolfenstein - Enemy Territory
Or in another location you have selected by the install of ET.
Replace the old ET.exe and ETDED.exe by the new ones from the 2.60b patch.

2.60b patch for Windows
2.60b patch for Linux

Thanks to ZoeterRonald for letting me copy :C
*sticky* plz

Good post, Thanks.

Stickied