DFS not replicating and Error 1053 occurs when trying to restart DFSR service

DFS replication has stopped replicating on all of our DFSR groups within Windows Server 2012.

When trying to run a DFS health report, it takes up to an hour to complete with the following error: Communication errors are preventing replication with 'server name'

Upon trying to restart the DFS Replication service, the following error appears:

'Windows could not stop the DFS Replication service on Local Computer. 
Error 1053: The service did not respond to the start or control request in a timely fashion.'

Any advice/recommendations of where to go from here would be much appreciated.

Thanks.