We've seen similar issues here after upgrading from v1 to v2. The v2 client doesn't seem to play nice with and the Microsoft Threat Management Gateway 2010 server blocks the Spark client as it sees Spark as a "flooding" exploit and blocks the traffic (0xc0040037 FWX_E_TCP_RATE_QUOTA_EXCEEDED_). We have a job HD0009094553 open with support to investigate this, but at the moment, we're just being told to Turn off the blocking as the fix, which isn't considered an appropriate response by our security people.
Wayne
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