MSExchange Web Services - Event ID 26 - Exchange certificate expiration question

  CN=exchange2010-MYHOST-CA

[Serial Number]

  9999999900000000000B

[Not Before]

  26/01/2012 18:07:28

[Not After]

  25/01/2013 18:07:28

[Thumbprint]

  G6G5C899B0B069CA76377A9A99BE5DF8081AB99B

will expire on 25/01/2013 18:07:28.

However, upon trying to renew the certificate, the following happens:

[PS] C:\Windows\system32>Get-ExchangeCertificate -thumbprint "G6G5C899B0B069CA76377A9A99BE5DF8081AB99B" | New-ExchangeCertificate
WARNING: This certificate will not be used for external TLS connections with an FQDN of 'exchange2010.MYHOST.local'
because the CA-signed certificate with thumbprint 'G6G5C899B0B069CA76377A9A99BE5DF8081AB99B' takes precedence. The
following receive/send connectors match that FQDN: Default exchange2010.

Confirm
Overwrite the existing default SMTP certificate?

Current certificate: 'G6G5C899B0B069CA76377A9A99BE5DF8081AB99B' (expires 12/03/2015 14:39:51)
Replace it with certificate: 'G6G5C899B0B069CA76377A9A99BE5DF8081AB99C' (expires 12/12/2017 13:20:26)
[Y] Yes  [A] Yes to All  [N] No  [L] No to All  [?] Help (default is "Y"): n

Thumbprint                                Services   Subject
----------                                --------   -------
G6G5C899B0B069CA76377A9A99BE5DF8081AB99C ....S.     CN=exchange2010.MYHOST.local

Any ideas on this?

Many thanks,

Andy