I just got AE and began working on my first project. After a few hours of work, I decided to save it and go take a break (I closed the program). When I came back, I opened the saved file the project loaded. However, when I click play [or do anything for that matter] the programs goes unresponsive and I have to close it just to reopen it and face the same issue.
My compter's specs:
Intel Core i7, 2.80GHz
64-bit Operating System [Windows 7 Professional]
Well, what did you actually do? And what version of AE? Depending on what you were using, there could be any number of reasons. One possibility could be issues with the media cache, another Rotobrush (in CS5 and beyond). In both cases you could simply see the program re-caclulating data because nothing is cached and that could take a while. Anyway your info is far too vague. Provide more details and in particular tell us whether there is actually any processing going on when AE goes unresponsive by monitoring task manager...