My SBS 2011 servers use the standard built-in Windows backup enginer as well as MozyPro online - successful. I've just noticed a very high number of handles on wbengine.exe. One server - looking at it right now - has 3,614,186 open handles. I seriously doubt this is normal but couldn't find anything online to tell me. Hence my question as this server is extremely slow. I've also noticed that Exchange uses all available memory (by design) and this has killed the system so I reduced the Cache size to 4GB (server has 16GB of RAM) and this improved the performance so now just need to understand wbengine.exe.