Sometimes I can upload to Facebook, sometimes I can't. When I can't, I get an unkown error message. Any suggestions? It's frustrating because the process usually takes an hour or so and then I get the error message at the end of the process. Maybe Premiere Elements has an issue or there may be something better to use?
It sounds like it's an issue at Facebook's end. Although it also may be because your videos are longer than 10 minutes or are compose of videos that require a lot of processing. But most likely it's just a Facebook traffic jam.
The easiest solution is to just output your video from Premiere Elements and upload it manually. You can do that by going to Publish & Share/Computer/AVCHD and selecting one of the YouTube or Vimeo presets. An AVC file is the ideal format for producing high-quality videos for YouTube, Facebook and Vimeo.