Merge Replication Error, cannot create a new snapshot

I have a Merge Replication over Internet setup on a MSSQL Server 2008 R2. 

Had this problem happen once already, and I had to re-create the publication on the server and re-create all subscriptions at clients. So, I'd like to avoid doing that again if possible.

The replication worked fine for a few months, and then it just stops and comes up with an error. This is the first error that I can see in the replication monitor

Error messages:
The merge process was unable to create a new generation at the 'Publisher'. Troubleshoot by restarting the synchronization with verbose history logging and specify an output file to which to write. (Source: MSSQL_REPL, Error number: MSSQL_REPL-2147200994)
Get help: http://help/MSSQL_REPL-2147200994.

Trying to sync with that publication from different machines results in timing out. This is the error

Error messages:
The replication agent has not logged a progress message in 10 minutes. This might indicate an unresponsive agent or high system activity. Verify that records are being replicated to the destination and that connections to the Subscriber, Publisher, and Distributor are still active.

There is also a red circle with an x in it next to every icon in the replication monitor.

I tried creating a new snapshot, but that just kept showing this message in the status "[0%] Setting up the publication for filtered articles".

Anyone know why this happens and is there a way to fix it without re-creating the publication?

Thanks!

Dragan