CiviMail Upload problems.
PROBLEM: I completed the step of naming my mailing, selecting recipients, and then try to upload the message. Upon attaching files and clicking upload files, it returns me to step one.
RESPONSE 1: This happened to me recently. I'm pretty sure it was because I was trying to upload a 1.5M file and the php upload limit was 1M. This was on import it gave me a wierd error message and kept me on the first screen of import (I think it said file required for import). I have not traced it, but i suspect php traps the error and does not send the file to the recieving script (in this case CiviCRM).
RESPONSE 2: Have your created the files/civicrm/upload/ directory per the installation instructions, and can you confirm it is writable by the web server?