You could duplicate the AE project file, move it to the location of the collected files, open it and relink the footage. Then when you relink one file, the others usually also relink.
After that, you save the project file, give it to your friend, and there should be no problems.
Hi Dave -- I realize we can do that. But with lots of files in different folders, it's a big pain.
How come "Collect Files" doesn't collect the project any more?
I'll assume this means that AE didn't ask you if you wanted to save the project BEFORE it started collecting files.
If so, it's obviously wrong and we'll need more information about your system, OS and versions of software for diagnostic purposes.
Dave - it does ask to save the project before collecting the files, but it doesn't add the project itself to the folder. In previous AE versions it would collect the files into a "Footage" folder and then also put the project itself into the overall folder with the footage.
Now it doesn't include the AE project. At least that's the way it's working for me.