This question might not be best posed in this forum, but I'm hoping there are enough people here who use Windows Home Server 2011 that the answer might be easily found.
I use Windows Home Server 2011. I have four other client PC's connected to it (my two HTPC's, my workstation and my notebook). WHS manages my backups, but it will not backup my primary HTPC. The backup consistently fails at 1% complete. The problem seems to be related only to this machine.. all other clients back up regularly with no issues.
The HTPC in question is the first one I built several years ago. It is an MSI Media Live Diva 5.1. The board I had originally purchased worked for about a year, and failed. I found two other identical boards on Ebay about a year ago and used one of those as a replacement. It worked for about four months and also failed. The third replacement also failed in about the same time frame. All for the same problem (domed caps). I replaced the power supply, had all three boards repaired and have now been up and running trouble free for about six months.
In each (short) lifetime of the motherboards, I made no changes to my Windows 7 install, I simply swapped out the board, booted the system up and ran with it, so I think that I may have confused the backup feature in my server. I'm not sure if WHS2011 keeps track of the specific hardware configuration of each machine (it probably does) or what effect changing the motherboard may have had on it, but that seems to me to be the root of the problem. I'm just not sure what to do about it. I have reinstalled Windows 7 for other reasons, but the backup problem remains. Some googling of this problem also offered some troubleshooting, but ultimately not much help.