I have someone who is experiencing random connection problems on the clients such as slow or no connections to mapped network shares. Event id 10009 keeps being recorded in the domain controller logs. DCOM was unable to communicate with the computer MARK-PC.pmc.local using any of the configured protocols. It has a range of different computer names within the same events. As far as DCOM is configured it's only setup to use TCP-IP. Server - Windows Server 2008 Standard FE System type: 64-bit Operating System Clients: 24 XP Pro 2 Vista Pro 2 Vista Home (should they be using home in an environment like this?) I have attached the last 256 logs from Application & System as of yesterday evening at around 5pm'ish. I've checked again this morning and looks like the same error has already been re-occurring. Can anyone give me any suggestion as to where to go with this? Thanks.