SQL-Server 2008 R2 Mail Configuration failed

SQL-Server 2008 R2 Mail Configuration failed

I have a failover SQL server that I need to configure DB mail for. I got
it working on the primary database and all configurations are mirrored to
the failover server. The issue is that the 2nd server has a different host
name and the send mail test fails:
Object reference not set to an instance of an object.
I cannot change the host name of the secondary server and I only need
email working for the failover. When I try to delete the account, it says
that it's successful, but when I try to re-add it I get the below error.
TITLE: Configuring...
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Unable to update account Hot Swap Mail for SMTP server
Microsoft.SqlServer.Management.SqlManagerUI.SQLiMailServer.
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ADDITIONAL INFORMATION:
Set mail server login password failed for MailServer 'Incorrect Host
Name'. (Microsoft.SqlServer.Smo)
For help, click:
http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=10.50.4000.0+((KJ_PCU_Main).120628-0827+)&EvtSrc=Microsoft.SqlServer.Management.Smo.ExceptionTemplates.FailedOperationExceptionText&EvtID=Set+mail+server+login+password+MailServer&LinkId=20476
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An exception occurred while executing a Transact-SQL statement or batch.
(Microsoft.SqlServer.ConnectionInfo)
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An error occurred during decryption. (Microsoft SQL Server, Error: 15466)
For help, click:
http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=10.50.4000&EvtSrc=MSSQLServer&EvtID=15466&LinkId=20476
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BUTTONS:
OK
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