Yes, I know the VideoCopilot forums are full of reports of such issues, but I'm afraid we never got to the bottom of any of this. There certainly is an issue with the PNG CoDec somewhere, but whatever it is, it's a specific combination of things. The only thing anyone can tell you is to try to reinstall Quicktime and see if it makes any difference. posssibly you could even try older versions of QT. Other than that, converting the files to PNG image sequences or TIFFs is always an option. You can use VLC or otehr video players/ converters for this.
I had the same problem.... but i deleted Quicktimeplayer and used Quicktime player 7
Hey man i made an account just to reply to this, i had the same error come up while i was importing video files so i had a look around and found that it had something to do with the language/coding not being recognised, so i looked closer into the footage and tried different method of importing the file and later realised that after effects didnt recognise some of the characters in the file path way, the original folder was created using a macbook, windows recognises the language but after effects didnt, so i moved the file to my desktop and tried to import it again and presto it worked fine, you may not have the same problem but i thought just incase you do, you should try moving the file,
if not heres a thread for the error:
hope that could be of some help.
I just came across this error message yesterday for the first time. After checking the directory and path of the files I wanted to import I realized that one directory name included a character to that AE was not able to interpret. I renamed this directory and everything worked fine. So check your directory and file names and make sure to use no special characters.
System: MacBook Pro, MacOS 10.6.8, After Effects CS6 (test version)