This issue occurs when your registry is not set up correctly. Common issues that cause this is copying/moving BF2 folders, registry cleaners, and system restores. As for copying/moving folders, you cannot just simply copy a folder to a new computer or a different location and expect it to work, there is an installer there for a reason...
Anyway, the fix if you are absolutely certain you have BF2 v1.5 installed:
Instructions for modifying your registry to be showing the BF2 installed version as 1.5:
- If you are running a 32 bit operating system:
- Download the file: http://realitymodfiles.com/ancient/bf2_ ... re_x86.zip
- Extract and run the .reg file and press yes to merge the settings with your registry
- If you are running a 64 bit operating system:
- Download the file: http://realitymodfiles.com/ancient/bf2_ ... re_x64.zip
- Extract and run the .reg file and press yes to merge the settings with your registry
