You can't simply start DCRServer by itself as that will not start all of the dependent processes. It may also be that this error doesn't really indicate that DCRServer is down, but rather there is some other problem on the server.
However, you might try restart CiscoWorks Daemon Manager. On Windows:
net stop crmdmgtd
net start crmdmgtd
On Solaris:
/etc/init.d/dmgtd stop
/etc/init.d/dmgtd start