You may try following:
1. Backup only Shadow copy component.
2. Reinstall the Remote agent, refer following technote to install Remote agent however to uninstall Remote agent use Add remove programs.
http://support.veritas.com/docs/253058
http://support.veritas.com/docs/265736
Hope this helps.
If the issue still exists then please let us know the exact error message or any Event ID(s) if any.