Issue with MSSQL 2017 CLR referencing IBM.MQ (amqmdnetstd.dll)

All,

I've been going at this for a couple of days now and hoping someone out here has experienced this and knows how to solve it. I am migrating a SQL Server 2008 R2 database running on Windows Server '08 to a new SQL 2017 Enterprise installation running on Windows Server '16. In my current database, I have a CLR I developed many years ago to facilitate coms with IBM MQ servers. This CLR uses the amqmdnet assembly from IBM. I went the CLR route because most of my applications that that would need to use MQ to get or put messages are web based and SQL Server gave me a clean platform to facilitate those interactions (websites were already heavily interacting with the database.) This CLR has worked great and given me no issues over the years.

Fast forward to now. The original assembly, amqmdnet, seems to be incompatible with SQL Server 2017 which is fine... it is depreciated anyway. The new assembly is amqmdnetstd.dll and is built on netstandard v2. I have been able to successfully rebuild my CLR assembly with the new MQ assembly and required netstandard.dll and .NET assemblies. I loaded the latest .net assemblies (4.8) and ensured that netstandard was version 2. My test CLR is a bare bones MQ PUT function to limit possible fail points to a minimum. I can run this exact code in a console application with no issues, and I can run it on a website hosted on the same server with no issues. Its only on the SQL Server installation that it fails.

If I remove any try/catch on the CLR, I get the following stack trace:

Msg 6522, Level 16, State 1, Procedure sp_clr_MQ_SimplePut, Line 0 [Batch Start Line 25]
A .NET Framework error occurred during execution of user-defined routine or aggregate "sp_clr_MQ_SimplePut": 
System.TypeInitializationException: The type initializer for 'IBM.WMQ.MQQueueManager' threw an exception. ---> System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.ArgumentException: The path is not of a legal form.
System.ArgumentException: 
   at System.IO.Path.LegacyNormalizePath(String path, Boolean fullCheck, Int32 maxPathLength, Boolean expandShortPaths)
   at System.IO.Path.InternalGetDirectoryName(String path)
   at IBM.WMQ.ManagedCommonServices..ctor()
System.Reflection.TargetInvocationException: 
   at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck)
   at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark)
   at System.Activator.CreateInstance(Type type, Boolean nonPublic)
   at System.RuntimeType.CreateInstanceImpl(BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes, StackCrawlMark& stackMark)
   at System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes)
   at System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture)
   at System.RuntimeType.InvokeMember(String name, BindingFlags bindingFlags, Binder binder, Object target, Object[] providedArgs, ParameterModifier[] modifiers, CultureInfo culture, String[] namedParams)
   at IBM.WMQ.CommonServices.CreateCommonServices()
   at IBM.WMQ.CommonServices.TraceConstructor(String objectId, String sccsid)
   at IBM.WMQ.Nmqi.NmqiEnvironment..ctor(NmqiPropertyHandler nmqiPropertyHandler)
	...
System.TypeInitializationException: 
   at IBM.WMQ.MQQueueManager..ct...

Here is the full CLR with only the connection details redacted:

using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.SqlTypes;
using Microsoft.SqlServer.Server;
using System.Collections;
using IBM.WMQ;

public partial class StoredProcedures
{
    [Microsoft.SqlServer.Server.SqlProcedure]
    public static void sp_MQ_SimplePut (SqlString strMessage)
    {
        //Conection Details
        string  strHostName     = "xxxxxxxx.xxx.xxx";
        int     intPortNumber   = xxxx;
        string  strChannel      = "xxxxxx.xxxxxxx";
        string  strQueueManager = "xxxxxxxxx";
        string  strQueueName    = "xxxxxxxxxxxx";

        //Create Queue Manager Object
        MQQueueManager mqQMgr = null;   // MQQueueManager instance
        //Create Connection Properties
        Hashtable mqProperties = new Hashtable
        {
             { MQC.TRANSPORT_PROPERTY, MQC.TRANSPORT_MQSERIES_MANAGED }
            ,{ MQC.HOST_NAME_PROPERTY, strHostName }
            ,{ MQC.PORT_PROPERTY, intPortNumber }
            ,{ MQC.CHANNEL_PROPERTY, strChannel }
        };

        //Create Queue Manager Object
        mqQMgr = new MQQueueManager(strQueueManager, mqProperties);  //<-- This is where the exception is thrown

        //Create Queue Opening Options
        const int openOptions = MQC.MQOO_OUTPUT + MQC.MQOO_FAIL_IF_QUIESCING;

        using (MQQueue mqTargetQueue = mqQMgr.AccessQueue(strQueueName, openOptions))
        {
            // Define a WebSphere MQ message, writing some text in UTF format
            var msg = new MQMessage
            {
                CharacterSet = 1208
            };

            msg.WriteString(strMessage.ToString());

            // Specify the message options
            var pmo = new MQPutMessageOptions(); // accept the defaults

            // Put the message on the queue
           mqTargetQueue.Put(msg, pmo);

        }

        //Close Queue Connection
        if (mqQMgr != null)
            mqQMgr.Disconnect();

    }
}

My troubleshooting steps so far:

• I can run this exact code with no issues on both console app and asp.net site (ASP.NET site running on same server as the MSSQL installation.) Code doesn't appear to be the issue.
• When I load import this CLR assembly into the dababase, I also load the exact same assembly files referenced when I built the CLR.
• I created a new, clean database for this, so no carry over from a restored DB.
• This database is set as TRUSTWORTHY so the CLR Strict Security feature isn't going to cause any issues, plus I've tested this with Strict Security turned off with the same results.
• I have installed the latest .NET runtime (4.8) on the server itself.
• I have installed IBM.WMQ Client on the server.
• I have explicitly registered the amqmdnetstd.dll and netstandard.dll assemblies in the GAC.

If I put a try/catch in it gives me a less detailed exception which I've put below:

Exception.Message:
The type initializer for 'IBM.WMQ.MQQueueManager' threw an exception.

Exception.StackTrace:
   at IBM.WMQ.MQQueueManager..ctor(String queueManagerName, Hashtable properties)
   at StoredProcedures.sp_MQ_SimplePut(SqlString strMessage)

Exception.Source:
amqmdnetstd

Exception.GetType:
System.TypeInitializationException

So that's where I am. Everything points back to this being something with how SQL Server 2017 is interacting with this particular assembly. Hoping its just a ID10T error and someone on here says "Oh yeah, you just forgot to do _____!" One can hope, right?

Anyone encounter this before? Any suggestions?

Thanks!

John