Environment:
Exchange 2000 SP3 on Win2k SP4
BES 4.1.4 MR4

Issue:
I'm in the process of building a new BES so that we can perform a knife-edge and decommission the old beast of a machine that currently hosts our BES.

However, for the life of me, I can't find an appropriate update from MS that will bring the ESM on the BES (and thus the mapi32.dll file) to a version that matches what's on the Exchange 2000 server (v6.0.6619).

Any assistance would be greatly appreciated, I'm at my wit's end...

You should be able to install Exchange 2000 ESM on the new machine and then apply all the SP3 roll ups from Microsoft. If you end up being heigher than the version on Exchange that is fine.

As far as I know after SP3 they had roll ups that brought the version higher.

I found this n MIcrosoft's web site for Exchange 2000:

Download details: Security Update for Exchange 2000 Server (KB931832)

That might help.