Connection in transaction is null / transport-level error

Connection in transaction is null / transport-level error

Hi All,

I got this error in production in the module "RuntimePlatform
". Still using the 4.2 enviroment unfortunately.

Connection in transaction is null (TransactionInfo Status: Connection.State=='Closed', Free='False', CreationTime='12/17/2011 12:58:40 PM', LastChange='12/18/2011 12:58:41 PM', ReaderCount='0'). (Pool Status: Total=1, Free=0)
Transaction discarded from pool. Obtaining another transaction and retrying


Beside this error I also get this error frequently. I don't know if these are related. The happen on diffrent timestamps.

A transport-level error has occurred when sending the request to the server. (provider: TCP Provider, error: 0 - An existing connection was forcibly closed by the remote host.)

Anyone an idea? I hope so.. cause i'm running out of them.

Thanks and best regards.


The upper error seems to be an application pool error (IIS). Don't know exactly what it means, but I think it has something to do with maximum connection or application pool not running.

The other error I don't know what it could be.

Kind regards,
Hi Michiel,

Can you check in Windows "Event Viewer" for any logged information at the time you got this error and post that information?

Ivo Gonçalves

The top one is not related to IIS: it pertains to DB connection pools. Essentially, when you transiently lose connection to the SQL Server, all the transactions that exist in the pool become invalid because the "parent" connection was shut down. Unfortunately there is no way to determine if a transaction in the pool is still alive without making a query using it (that will blow up).

Since we don't want to be doing queries needlessly all the time just to check if transactions are still alive (because that has a cost and they are normally ok) we opted to catch (and log) these invalid transactions and rebuild the pool instead.


Hi all,

Thanks for the reactions.

The eventlog wasn't show additional info. So that wasn't helping me.

The more we look in to it the more it looks like a network problem.
We found out that in the active sessions all the request are from the same server but with different mac adresses.

So there might be a routing problem somehow.
The registery in windows also has multiple mac addressen registered.

Yesterday we killed a few sessions and as a result my OS license went invalid.
So my guess is that the session that is used for the license check has a diffrent mac adres.

We are trying to fix all this first.

Best reagrds.