I just went through a few hours of Electrum not syncing with the network.
After a bit of searching I found the simple solution - upgrade my Electrum. I had an older version and it wasn't happy after the SegWit fork. So if you're having trouble you can give this a shot.
Here is the page you need to go to: Electrum
Before doing anything, verify you're at Electrum.org. The link should be fine but it doesn't hurt to check.
art source: pic