Issue with Internet Explorer Launching and Closing Repeatedly


I have a very strange issue with MailStore.

The last time I used it (Version 13) was 2 or 3 weeks ago; everything worked fine.

Now, when I try and do just about anything, old Internet Explorer is launched and closed, repeatedly, automatically, forever. I have to get lucky with Task Manager to even kill it.

I just upgraded to Version 22 with the same results.
I rebooted – same issue.
I reinstalled Outlook email – with the same results

Does anyone have any idea of what this may be caused by, and how to fix it ?

One error message I get is: Internet Explorer HTML viewer: Unable to load HTML.

Hi Bob,

You’re an early victim of the ending of Internet Explorer.
On June 15 2022 will IE be retired.
You’ve had 2 yrs to change to Edge,
Edge now comes with backwards IE compatibility.

Install Edge or another up-to-date browser and set it as default.

MSH uses part of the default browser to login to your webmail among other things

Hope this helps.

Peter E.


Thanks for the help.
But I still cannot get MailStore to work properly.
I completely uninstalled Internet Explorer. That got rid of the IE launching and closing repeatedly issue.
But now whenever I try to open one of my stored emails I get the error message: “Internet Explorer HTML viewer: Unable to load HTML.”
I have already made Microsoft Edge my default browser.
But still get the same error message.
Is there something in MailStore that needs to change to recognize Edge ?

Any further help is appreciated.

Please try to install Internet Explorer again and check if the error message disappears and the emails are shown normally.

Really? MailStore relies on Internet Explorer code?
I’ve been having this same issue and find the above suggestions unbelievable.
MailStore suddenly doesn’t look like the place I want to store my email any more. Too bad… I really liked it.

A bit more specifically, MailStore uses Microsoft’s libraries for a variety of things including encrypted connections to remote servers, managing local secrets (this applies to MailStore Server more than Home), rendering HTML within MailStore itself, and various other functions provided by the .NET libraries.

In the case of rendering HTML, this uses the same library that Internet Explorer itself was built on top of, although it was migrated into Windows over a decade ago.

This was a great solution when it was developed as Microsoft maintains the HTML libraries within Windows so you are automatically protected against certain classes of bugs/vulnerabilities just by installing Windows Updates (and without needing to install a MailStore specific update).

This is actually very common and much more widespread that you might imagine, with Outlook itself using a modified version of the same.

I think the problem you are seeing is related to how Edge and Internet Explorer act together as Microsoft tries to push users into Edge’s IE mode (another example of an application that uses IE’s HTML libraries, incidentally) as Microsoft is working toward depreciating Internet Explorer itself – But even when this happens completely, the underlying HTML libraries will continue to exist and be used.

…and in the mean time, I see no text in my emails that are stored in MailStore.

To confirm, when you see no text in your emails that are stored in MailStore, is this with missing Windows components?