Drupal is not so easy to move from one server to another. Sometimes it works, sometimes it doesn't. I move a site from a server running MySQL 4.1 to MySQL 5.1 today and when I hit the page, I got a completely blank screen.

Hm.

I added set_error(E_ALL) to the top of my settings file and got a bunch of missing index messages (which apparently is normal) and then a dump of binary looking data.

After inserting some echo statements throughout the code, I realized the problem was with the cache.

DELETE FROM cache

Now it works.