A "for info" - Gmail and PropertyAccessor on IMAP don't mix

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A "for info" - Gmail and PropertyAccessor on IMAP don't mix
Using PropertyAccessor while Sending emails through GMAIL 
Pino Carafa




Posts: 81
Joined: 2016-09-28
Hello Andrei,

This is just one that's "good to know". I'm not looking for any "solution" to this as it's clearly Gmail that's causing the problem.

I created an Outlook profile pointing at GMail using IMAP

I sent a message and the message is processed through ItemSend

In ItemSend I set a Property through the PropertyAccessor.

The email arrives in the Sent Items and I try to read the same Property from the PropertyAccessor. A COMException is raised as the requested Property cannot be found.

I then created another Email address through Zoho. Once again I set up IMAP access and I do the exact same thing. This time it works fine. From the Sent Item by a ZOHO account it can find the Property without a problem from the PropertyAccessor.

So it looks like Gmail decides to strip out Properties it doesn't like while processing an email for sending. I can't think of another explanation....
Posted 22 Oct, 2019 07:48:06 Top
Pino Carafa




Posts: 81
Joined: 2016-09-28
And Zoho has its own problems... I created an outlook profile looking at Zoho through IMAP and I found that Sent Items appeared TWICE in the "Sent" folder. Here I am hacking away at my add-in trying to figure out where I'm messing up.... and then I had the bright idea to remove ALL add-ins including my own.

And the Sent items are STILL doubled

It would be funny if it weren't so tragic.

I think we'll give our IMAP customers VERY limited functionality after this :-)
Posted 22 Oct, 2019 08:53:41 Top
Andrei Smolin


Add-in Express team


Posts: 16673
Joined: 2006-05-11
Hello Pino,

IMAP folders is an Outlook store flavor such as PST and Exchange. The problem is: IMAP folders are implemented by third-party vendors. And what you see is a result. Please be sure that other IMAP Folders providers will have issues of their own.

I think we'll give our IMAP customers VERY limited functionality after this :-)


It may be possible to have one more provider-specific add-in or even a set of VBA macros that might solve some of provider-specific issues. This is a very long way with no guarantee of success, though.

Regards from Belarus (GMT+3),

Andrei Smolin
Add-in Express Team Leader
Posted 23 Oct, 2019 03:31:29 Top
Pino Carafa




Posts: 81
Joined: 2016-09-28
"This is a very long way with no guarantee of success"

Indeed. And considering that we primarily cater for people using Exchange I don't think we should "bust a gut" trying to placate every IMAP implementation out there. I might spend a little time looking at an IMAP connection to an Exchange server (why would anybody do that though)..... A *little* time. :-)
Posted 23 Oct, 2019 07:22:18 Top
Andrei Smolin


Add-in Express team


Posts: 16673
Joined: 2006-05-11
Pino Carafa writes:
for people using Exchange


Exchange is an area bigger than you can think of. https://social.msdn.microsoft.com/Forums/aspnet/en-US/901d03a3-8e9b-4d27-8c91-76f876ec38fe/outlook-2016-produces-an-extra-itemchange-event-after-an-appointment-is-created?forum=outlookdev.

Right now I try to find a solution to the issue with conflicts from your other thread. The project quickly becomes a bit too big; the bit is growing as well. One more case of "no guarantee of success".

Regards from Belarus (GMT+3),

Andrei Smolin
Add-in Express Team Leader
Posted 23 Oct, 2019 07:53:58 Top
Pino Carafa




Posts: 81
Joined: 2016-09-28
<little voice> Help.

Thankfully our interaction with Appointments is not nearly as ambitious as what we're trying to achieve with Emails. I think I'll take this as a fair warning to not try to do too much there, either!

As for my original post.... A friend of mine suggested, when I mentioned that we added Properties through the PropertyAccessor with names like "CaseReference" that perhaps Gmail is being "overly strict" on naming conventions. He suggested I should see what happens when I give them X- prefixed names, e.g. "X-CaseReference"

And won't you know it.... it works.
Posted 23 Oct, 2019 10:36:10 Top
Andrei Smolin


Add-in Express team


Posts: 16673
Joined: 2006-05-11
Wow! Perfect! Just perfect!

Regards from Belarus (GMT+3),

Andrei Smolin
Add-in Express Team Leader
Posted 24 Oct, 2019 03:14:20 Top