AC 11: Missing PLP!!!

[Laura Yanoviak]

We have been using AC11 for a year-and-a-half, and this has just started happening in the past 2 weeks: we've had three PLP files gone missing! A user will be signed into a project and notice that the PLP is gone after trying to (unsuccessfully) perform a Send & Receive. I can only assume this has something to do with our network, but since I'm IT-challenged, I can't begin to figure out how this is happening. We do have contracted IT help, but in the meantime I'm wondering if anyone else has experienced this, as it's quite disturbing...