Before you configure BizTalk, you have to configure the MSDTC to allow remote client
Go to: Administrative Tools> Component Services >
Extract Component Services until you find My Computer, and right click and choose property
In property go to MSDTC tab and click on Security Configuration button.
In Security Configuration you must activate (V check the box):
-Security Settings> Allow Remote Clients
-Security Settings> Allow Remote Administrators
And that will do the trick.
By the way, if you having also the OLAP on a remote server from the BizTalk, you have to install OLAP locally too, but DON'T do full installation, just install:
SQL Server 2000 Analysis Services Client Components –
-Decision Support Objects (DSO).
And of cores don't forget to install The Service Pack too.
Otherwise you will get another error.
Best of luck
Bizon