Hello Artur,
It appears you can backup the lotus database via microsoft network but not via a user defined share using ip adress.
In this case please check the entries in the hosts file on both servers, verify that the the ip address and the machine names are mentioned on either of the servers.
You can also verify with the command ping -a name of server, which will return the ip addtess to which the name is being mapped.
Additional Information :
For information on the recent VERITAS Backup Exec security vulnerabilities, including links to the downloads for the necessary hotfixes, please refer to the following document:
Patch summary for Security Advisories VX05-001, VX05-002, VX05-003, VX05-005, VX05-006, VX05-007
http://seer.support.veritas.com/docs/277429.htm
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