Activesync error 0x85010017 on X1 with Windows Mobile 6.1

My Sony Xperia X1 has been syncing fine with my Exchange server for several months but since the USA upgraded their server last weekend I cannot sync and keep getting error codes.

I have the following information from my USA server manager regarding what changed during the upgrade:
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Old server: Exchange 2003sp2 front-end
New server: Exchange 2007sp1-ur8 CAS+HUB

The address did not change

The certificate is valid.
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I have tried to delete my PC device and the exchange server on my phone and then reboot both, but this doesn't seemt o have helped with anything?

Any help would be appreciated to get my X1 to receive emails again.

Thanks
Steve

I deleted the device on my laptop and also active sync connection & settings on my phone, power off on both and new restart on both.

My phone has sync'd all my contacts & files OK but Microsoft Exchange is still not working.....

Now I get error message
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Microsoft ActiveSync
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Cannot connect with current connection settings. To check your connection settings, select Start, then Settings, then Connections.



Support Code:85020006
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OK
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Latest attempt to sync with Microsoft Exchange give sthe following error:-

0x80072F06

Has anyone any diea's?
Thanks

The problem can be third party application like i had this error because i had installed translator program so after uninstalled it no problem. another things you can try change the view on Calendar to show All Appointments and then delete 6 duplicate calendar. This error might be caused by the presence of a large volume of items in the first synchronization. Or, the error might result from specific large items, such as calendar items with many meeting attendees.v check here http://support.microsoft.com/kb/915152