mount: RPC: Program not registered

Had problems one time where my network servers did not want to nfs mount shares on my main file server. When mount was run the following message appeared:

mount: RPC: Program not registered

After some searching in the google archives I found this:

check your local rpc services:

rpcinfo -p

on a debian 3 nfs client you should see something like:
program vers proto port
100000 2 tcp 111 portmapper
100000 2 udp 111 portmapper
100021 1 udp 1024 nlockmgr
100021 3 udp 1024 nlockmgr
100021 4 udp 1024 nlockmgr
100024 1 udp 1025 status
100024 1 tcp 1025 status
100003 2 udp 2049 nfs
100003 3 udp 2049 nfs
100005 1 udp 1026 mountd
100005 1 tcp 1026 mountd
100005 2 udp 1026 mountd
100005 2 tcp 1026 mountd
100005 3 udp 1026 mountd
100005 3 tcp 1026 mountd

then do the same on the server, you should see something similar. if you are not I recommend shutting down all nfs and rpc services (/etc/init.d/nfs-common stop), then start portmap, and restart nfs-common, and run rpcinfo -p see if they show up, if they still don't, then check to be sure theres no firewall on the local machine that would block connections, and stop all the services again including portmap and check netstat to be sure the socket is closed (netstat -an | grep 111 should come back with nothing) and try again ..

If it still doesn't work do the same to the server.

Of course my commands didn't exactly match. In slackware the rpc commands are in /etc/rc.d/rc.inet2. I just killed all the rpc processes and re-ran rc.inet2. Now it works like a champ.