How to purge MSMQ system queue journal programmatically on a workgroup installation?

Question

I try this: MessageQueue mq = new MessageQueue(".\Journal$"); mq.Purge();

It work good on XP. But, on windows 2003 server, I always have this error : "A workgroup installation computer does not support the operation."

Indenture

Answer 1

Try using format name like so:

MessageQueue mq = new MessageQueue("DIRECT=OS:computername\SYSTEM$;JOURNAL");
mq.Purge();

I think that system queue can't be access by path. You have to use format name.

look at Yoel Arnon's comment at the bottom of the page.

Parvenu

This is incorrect, the code won't even compile, (because of the backslash), see my answer for the correct syntax (your link did give me the proper answer, however). – Daisydaitzman

Answer 2

The correct format for system queues:

FormatName:Direct=os:.\\System$;JOURNAL

I've tested this format on Windows 7 and Windows 2003.

(the dot after os: means the localhost/local computer)

var systemJournalQueue = new MessageQueue("FormatName:Direct=os:.\\System$;JOURNAL");
var systemDeadLetterQueue = new MessageQueue("FormatName:Direct=os:.\\System$;DEADLETTER");
var systemDeadXLetterQueue =new MessageQueue("FormatName:Direct=os:.\\System$;DEADXACT"));

systemJournalQueue.Purge();

or if you want to keep N days of messages you can do this:

private static void PurgeQueues(int archiveAfterHowManyDays, MessageQueue queue)
{
    queue.Formatter = new XmlMessageFormatter(new Type[] { typeof(System.String) });
    queue.MessageReadPropertyFilter.ArrivedTime = true;

    using (MessageEnumerator messageReader = queue.GetMessageEnumerator2())
    {
        while (messageReader.MoveNext())
        {
            Message m = messageReader.Current;
            if (m.ArrivedTime.AddDays(archiveAfterHowManyDays) < DateTime.Now)
            {
                queue.ReceiveById(m.Id);
            }
        }
    }
}

Daisydaitzman