Strange COM exception in BizTalk
A while ago I had serious problems with BizTalk. For some obscure reason the BizTalk engine would throw some XLANG errors and stop processing all messages. A restart of the hosts would fix the problem for a while but after some time the same problem would occur and BizTalk would effectively stop processing. (orchestrations would be marked as active but nothing happens)
The funny thing is, these orchestrations were deployed on the BizTalk Server a long time ago and they never gave any problem. All of a sudden these problems started to appear. So I think the blame is probably in some kb^*&^(& hotfix somewhere.
I had a case with MS-Support (and for sure they had never seen this error) and even google will not tell you that much about it.
However, until now I have had two people contact me with exactly the same problem.
So I know I was not alone ! Since googling on this gives me very poor results I will put some details about what happened in this post.
Unable to cast COM object of type 'System.__ComObject' followed by No such interface supported (Exception from HRESULT: 0x80004002 (E_NOINTERFACE)).
When this happens you will find a lot of references to the guid 6C90EC05-4918-11D3-A242-00C04F60A533 (see bottom)
I have mentioned both MSDN threads that have this problem. The things we have in common are:
- Usage of the classic SQL adapter
- Typically, this problem occurs when the orchestration engine reaches a Call Orchestration shape or a Start Orchestration shape.
To isolate this problem we added a specific SQL Host that does all the work for the SQL Adapter. We hoped the next time we saw the error, we could see if it was caused by orchestrations or really by the SQL adapter. Cause then onlu the SQL Host would have a problem. We had everything set up to debug the BizTalk environment with the tools provided by MS and we were waiting for the event to happen. But unfortunately after we added a dedicated SQL host the problem never re-occurred. So the supportcase is closed now (without a definitive answer).
If you have had a similar experience please give a response to this post.