Error when importing bindings: "Failed to update binding information."

When importing bindings into a BizTalk application, the following error message might appear:

TITLE: Import Bindings
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Failed to update binding information. (mscorlib)
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ADDITIONAL INFORMATION:
Cannot update send port "MoAGSendPort". (Microsoft.BizTalk.Deployment)

Cannot update transport information (address "C:\temp\SHS\ut\1.mb510i1_%SourceFileName%"). (Microsoft.BizTalk.Deployment)

The following items could not be matched up to hosts due to name and/or trust level mismatches:
Item: 'FILE' Host: 'SendHost' Trust level: 'Untrusted'
You must do one of the following:
1) Create hosts with these names and trust levels and try again
2) Re-export the MSI without the binding files and have a post import script apply a suitable binding file. (Microsoft.BizTalk.Deployment)

While the message might be correct regarding the host name or trust level, a more common reason to the failure is that the host doesn't have an adapter handler specified that matches the bindings.

In the Admin Console, browse to BizTalk Server 2009 Administration > BizTalk Group > Platform Settings > Adapters and then look at the adapter mentioned in the message. In my case it says "Item: FILE", so the File adapter is where I'm heading and it is indeed missing a send handler for the SendHost host.

To add a send handler, right-click on the adapter (or in the detail view of the window) and select New > Send Handler...

Then select the host that needed the specific send handler and click Ok.

Restart the host instance in question and then try to import the binding again.