None whatsoever. Troubleshooting in After Effects requires a lot of information. Tell us about your computer (processors, memory, cards, storage), your software (OS version, AE version, Quicktime version), and the video footage in your project (typre of media container & codec).
Without information, we have use crystal balls, and they're not very reliable.
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA