Service start up error "The service name is invalid net helpmsg 2185"

Hi

Don't know if this is the correct forum for this, if not please point me in
the correct direction but have installed 8.3.6.1 in a windows 2003 64 bit
server, in the default directories for the program files, data on a
seperate drive, set up postgres as a local user with admin rights, but when
come to start the service get the following error. "The service name is
invalid net helpmsg 2185" I cannot find any service relating to postgresql
on the service list for the server. I have tried to start this both logged
on as the admin account for the server and as the postgres local account.

Any ideas please as to where I am going wrong

Thanks
Tim