So, I'm currently planning to upgrade my forum from 1.4.10 to 5.1. In preparation for this, my host moved me over to a different server that is running php 5.5, so I can meet the new recommended version. However, ever since this move happened (yesterday), my members have been reporting posts, new threads, and even conversation replies of theirs sporadically vanishing. These posts do appear on the forum for a brief period of time before simply disappearing. I checked the moderator logs in case someone was deleting them, but that checks out fine. One of my own posts vanished like this after I had confirmed it posted. The post, however, still exists in the database. This has happened with both new posts and new threads. Any ideas what the problem might be?