We placed 2 new 3550-switches in our existing network. Configured them both as vtp-clients. But no newly made or already-existing Vlan's are available after connecting to the router (which is configured as VTP-server, 3550-12G).
VTP-Revisions are checked and ok, all switches have same IOS.
In test-envirement both switches did pick-up all VLan-information from a VTP-server and so do all the other switches in our network.
We already tried a complete reset to factory-defaults, erasing all vlan-information, reconfigure and reload.
nothing works so far, except putting in the neccessary vlans manually in vtp-server-mode per switch.
But that's not why we run VTP.
Were the trunks up between the VTP server and the client? You can do a
sh interfaces fastEthernet 0/x trunk
You mentioned the test network. Did you get rid of all VLAN database information before you placed the switch in to production? Erasing the startup config is not enough to get back to factory defaults. Look in flash (show flash:). Look for a file called 'vlan.dat'. This is where your VTP information is stored. Delete this file to get to factory default. Then reconfigure the VTP information. My guess is that you have the incorrect VTP domain or the wrong VTP password. You can look at the VTP information if you like - 'sh vtp status'. You can also do 'more' on the file in flash.
You don't have to delete the file, when you connect this switch to the production domain, move it as transparent mode and then change to client.
regarding the synchronization mode, as mentioned above, make sure the trunking is on, and vtp domain name and passwords are same on all switches.
As was suggested by the other posters; check vtp domain (which is case sensitive), password etc.
If you are pruning vlans that is allowed on the trunk, make sure you allow vlan 1 (which you should not really use for anything else). VTP advertisement rides on vlan 1