That is an excellent question, and something I have not thought about before. You certainly can temporarily disable replication to other servers via File/Replication/Settings/Other.
To take the database completely offline, you could rename its file at the operating system level. I have not tried that, but it should work. There is also a C API call that seems to be designed for this purpose. I have not tried it either. It is NSFTakeDatabaseOffline. Go to the LDD Notes 4 and 5 forum and search for this function name. You will see a posting that shows how to call it from LotusScript without writing any C code. Let me know if it works!
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