1. How can my IT department fix this problem? (I told them to copy the COMPANY’s DOMINO DIRECTORY without ID’S and delete the old one...they said there will be caos)
USe ID recovery
To recover from loss of, or damage to, an ID file, recommend to your users that they keep backup copies of their ID files in a secure place -- for example, on a disk stored in a locked area. Losing or damaging an ID file or forgetting a password has serious consequences. Without an ID, users cannot access servers or read messages and other data that they encrypted with the lost ID. To prevent problems that occur when users lose or damage ID files or forget passwords, set up Domino to recover ID files.
2. at the “notes client machine” area, what it is written-what do those computer names mean?(are those the ones who opened that database)
3. Are there anly logs showing who copied the IDs to their computers?No
4. Are there any logs to see who accessed whose database with the UserID they copied?
no, the only thing you can have is "user activty" but it won't tell you who was behind the computer (If the ID was stolen)
From the Admin help
Issuing new public keys for a Notes certificate
If you suspect that an ID has been compromised because it was lost, stolen, or copied without permission, you can create a new public key for the ID. Creating a new public key allows you to maintain other parts of the ID -- for example, the encryption keys -- rather than create an entirely new ID, so that users can still use their old keys to decrypt encrypted email.
Notes users can create a new public key for the Notes certificate. The new public key must be certified before it can be used by Notes.
After certifying a new public key, you should set up servers to verify public keys. Public key verification involves matching the public key stored in the Domino Directory with the public key on the ID. Verifying public keys prevents an unauthorized user from using the ID with the original public key to access the server.
Note This is done in addition to the key verification done by validating the certificate presented by the user during authentication.
For more information on verifying public keys, see the topic To verify a Notes public key.