BizTalk Deploy Error: Could not enlist orchestration ‘MyAssembley’. Object reference not set to an instance of an object. (Microsoft.BizTalk.SnapIn.Framework)

Today after I deploy and configure a new version of an existence solution, I tried to start the application and it gave me the following error:


Could not enlist orchestration '<MyAssembly>, Version=1.0.0.0, Culture=neutral, PublicKeyToken=bcfb9271ae6d2402'. Could not enlist orchestration

NullReferenceException exception occurred while the XLANG/s runtime enlisted a service.
Error message:Object reference not set to an instance of an object.
Call stack:   at Microsoft.BizTalk.XLANGs.BTXEngine.OrchestrationMetadata..ctor(String assemblyName, String orchTypeName, Delegate satAssemblyCacheCallback)
   at Microsoft.BizTalk.XLANGs.BTXEngine.BTXServiceStaticState.PersistState(String mgmtDBServer, String mgmtDBName, String MsgBoxGroupName, String ApplicationName, String serviceAssembly, String serviceTypeName, Guid[] PortIDs, Guid[] LrpIDs, Delegate satAssemblyCacheCallback, ITransaction transaction)
   at Microsoft.BizTalk.XLANGs.BTXEngine.EnlistAppDomainHelper..ctor(String configDBServer, String configDBName, String msgBoxGroupName, String applicationName, String servicePath, String serviceTypeName, Guid[] portIDs, Guid[] lrpIDs, Delegate satAssemblyCacheCallback, ITransaction transaction)
       
Object reference not set to an instance of an object. (Microsoft.BizTalk.SnapIn.Framework)



CAUSE
This maybe happens because the DLL’s presents in the GAC are not correct, or they are missing.

SOLUTION
Remove all the DLL’s and then deploy afterward or update them in GAC, normally solves this problem.

SOLUTION 2
Remove all the DLL’s and then change the DLL version (for example 1.0.0.1) and deploy the solution also, normally, solves this problem

But because today I was a little lazy and my lab machine had several windows updates to do, I decided to make a restart to my environment and install all updates and then deal with this error  .

Then came the best part, I decided to make one more shot, without changing anything, just application start J and IT WORKS!!

SOLUTION 3
Restart your machine!

refer: http://sandroaspbiztalkblog.wordpress.com/2011/05/11/biztalk-deploy-error-could-not-enlist-orchestration-myassembley-object-reference-not-set-to-an-instance-of-an-object-microsoft-biztalk-snapin-framework/