There are several reasons and solutions to this error;
1. The most common problem is that you attempted to patch at a time that servers were on "overload" or the servers were under maintenance - simply try again.
2. A program or virus may be inhibiting Crossfire from running properly. Programs that usually do this are;
Xfire, Skype, or an Anti-Virus Program.
Solutions -
Disable any un-needed programs either manually or by using a program such as SmartClose.
https://www.snapfiles.com/get/smartclose.html
Add Crossfire to your Anti-Virus Program's "Exceptions List".
You may need to run a Virus scan on your entire Computer System - thoroughly complete this scan and restart your computer.
3. If you have not already you need to perform a
clean re-installation .
Tutorial;
https://forum.z8games.com/showthread.php?t=96897