Can't get Firefox Sync to work

I get an error in the bottom that pops up (in the same place as the Add-on Toolbar) that says:

"Sync has not been able to complete during the last 7 days. Please check your network settings."

Is there any fix to this? I'm running Firefox Portable 13.0.1 and my Portable Apps client is up to date as well. I believe that Firefox Sync worked in previous versions which is why I have it enabled now.