I believe this is something to do the computer, UAC and mandatory controls. See this: https://blogs.msdn.microsoft.com/patricka/2010/01/28/q-why-doesnt-drag-and-drop-work-when-my-application-is-running-elevated-a-mandatory-integrity-control-and-uipi/

TEST: Are you running Thunderbird program as administrator? Exit Thunderbird. If you usually start Thunderbird from a shortcut icom on desktop: Right click on the Thunderbird icon and select 'Properties' select 'Compatibility' tab uncheck checkbox 'Run this program as an administrator' click on 'Apply' click on OK

Then start Thunderbird and test again for drag and drop.

Hi reservations1, as a follow-on to Toad-Hall's reply:

Where are you dragging from? What I mean is:

• File Explorer or Desktop?
• Firefox 68?
• Somewhere else?

First off, thank you to everyone who replied (and those that will reply lol). Really do appreciate the help.

In response to Toad-Hall (why does that name sound familiar? Is it from something?)

So Thunderbird IS run as administrator. In fact we have to in order for it to be triggered to compose an email with an attachment generated by another program we use. I conducted your test with no changes. I read your article and think I understand some of it. I'm a mac guy at home and we have a similar but simpler setup for that lol. Anyway, so the UAC on our machine is set to the 3rd from bottom of 4 possible levels. On a mac you can choose to give apps exceptions. Does windows 10 have something like this where you can give programs the right clearance needed? In this case it sounds like file explorer would need to be run as administrator but maybe I sound foolish rn? Lol pls help

In response to jscher2000 typically from the desktop or a file explorer folder. I tried from the Firefox browser we use as default when I saw this question but got the same result.

Bump for attention

You cannot drag and drop from a lower privileged process to a higher privileged process, such as File Explorer running at Standard User/Medium Integrity to Thunderbird running at Administrator/High Integrity.

It sounds as though you're in a bind because you need to Run Thunderbird at High Integrity for one reason but it creates the other problem.

Is it possible to run File Explorer at an Administer integrity level?

Toad-Hall had asked that I try running thunderbird without admin privelege and I did, but it didn't solve the problem. So I'm not sure how to get those 2 on the same level

reservations1 said

Is it possible to run File Explorer at an Administer integrity level?

I'm sure there must be a way. However, when I go into Properties for the shortcut, then Advanced, it is grayed out on mine.

Not sure if Windows will over ride this but.... 'Task Manager' > 'Details' tab Right click on 'Thunderbird.exe' > 'Set priority' shows the level. Right click on 'Explorer.exe' > 'Set priority' to see what level is set.

The 'Explorer.exe' level apparently can be changed to same as set for Thunderbird but suggest you make a note of the original level just in case changes cause a problem and you can return to original setting....that's assuming Windows OS will permit it working around the UAC etc. It may only allow if privileges permit.

Alternatively, if your issue is due to a bug....see if stopping and creating a new 'Explorer' task will allow drag and drop. I found this link which offers a solution in this case. https://howtoremove.guide/windows-10-drag-and-drop-not-working/

I have as follows which explains why I have no problems with drag and drop. 'Thunderbird.exe' > 'Set priority' = Normal 'Explorer.exe' > 'Set priority' =Normal

I have a User Account set as admin, but Thunderbird shortcut 'Properties' does NOT have this selected 'Run this program as an administrator'.

Toad-Hall said

https://howtoremove.guide/windows-10-drag-and-drop-not-working/

I had actually found this page prior and tried it with no results.

So I took your direction and checked task manager and the priority levels for thunderbird, explorer and firefox are all the same, set a "normal"

Now I mention firefox because i can drag n drop an image there with no problems. I used it as a control but when I was checking this out I noticed that on the thunderbird contextual menu "UAC virtualization" is greyed out.

I recognize this as a problem or a clue but i have no idea what to do with it. Any ideas what this is signaling?

I would also like to add...I just tried a little experiment. I quit thunderbird and ran it normal without admin privilege to see if I could get access to UAC virtualization and it wasn't greyed out.

So then I tried drag n drop and it worked but of course our third party app (based on MS Access) wasn't able to trigger thunderbird to start a new addressed email with the generated attachment. (i realize i was asked to do this in the very first post, and I did with no result. But when doing it this time, I was in the actual directory instead of the shortcut and saw that the thunderbird.exe had run as admin turned on, on the exe itself. So my shortcut chagnes probably did nothing at the time)

I hope this can shed some light on what might be going on here....

Why not just upgrade the whole "user" to an admin user. You are picking away as a problem but you are not addressing the root issue. Your access based application requires admin privileges. Fix the access based application, or as all the accounting firms did for about 20 years, use admin mode for users because you have defective software that requires it.

Matt said

Why not just upgrade the whole "user" to an admin user. You are picking away as a problem but you are not addressing the root issue. Your access based application requires admin privileges. Fix the access based application, or as all the accounting firms did for about 20 years, use admin mode for users because you have defective software that requires it.

This sounds good on paper. Just went to try it after reading this, only to find out it IS. Settings>Accounts, it shows the user name, and underneath that it's a Local Account and underneath that, it says Administrator

bump for views and hopefully more help :D

Same problem in Firefox:

https://support.mozilla.org/en-US/kb/windows-administrator-launcher-process-error-fix

https://techdows.com/2019/07/fix-firefox-68s-file-drag-and-drop-issues-on-windows.html

Does Thunderbird have a -no-deelevate switch too?

Hi joopbraak, I don't think Thunderbird has anything like the Firefox 68+ "launcher process" that you need to counteract with a command-line switch.

I run UAC with User Account set as administrator.

If I right click on Thunderbird shortcut > Properties > Compatibility and select 'Run this program as an administrator' Task Manager > Details - right click on explorer.exe > Set Priority says 'Normal' and UAC virtualisation says 'Disabled' Task Manager > Details - right click on thunderbird.exe > Set Priority says 'Normal' and UAC virtualisation says 'Not allowed' In Thunderbird you cannot drag and drop to attachment.

If I right click on Thunderbird shortcut > Properties > Compatibility and UNCHECK: 'Run this program as an administrator' Task Manager > Details - right click on explorer.exe > Set Priority says 'Normal' and UAC virtualisation says 'Disabled' Task Manager > Details - right click on thunderbird.exe > Set Priority says 'Normal' and UAC virtualisation now says 'DISABLED' In Thunderbird you CAN drag and drop to attachment.

It does not only effect Thunderbird. You cannot drag anything from Explorer to an Application which is running as Admin. I believe Windows OS auto sets explorer.exe to run without admin as a security measure regardless of UAC and regardless of whether the User Account is set as administrator.

Someone posted a link in a bugzilla bug which mentions how to force explorer.exe to work at a higher level, but how this impacts other Applications I have not checked. Here is the link:

• https://superuser.com/questions/1060456/is-there-any-way-to-run-file-explorer-as-administrator-under-windows-10/1060578

Toad-Hall said

I run UAC with User Account set as administrator. If I right click on Thunderbird shortcut > Properties > Compatibility and select 'Run this program as an administrator' Task Manager > Details - right click on explorer.exe > Set Priority says 'Normal' and UAC virtualisation says 'Disabled' Task Manager > Details - right click on thunderbird.exe > Set Priority says 'Normal' and UAC virtualisation says 'Not allowed' In Thunderbird you cannot drag and drop to attachment. If I right click on Thunderbird shortcut > Properties > Compatibility and UNCHECK: 'Run this program as an administrator' Task Manager > Details - right click on explorer.exe > Set Priority says 'Normal' and UAC virtualisation says 'Disabled' Task Manager > Details - right click on thunderbird.exe > Set Priority says 'Normal' and UAC virtualisation now says 'DISABLED' In Thunderbird you CAN drag and drop to attachment. It does not only effect Thunderbird. You cannot drag anything from Explorer to an Application which is running as Admin. I believe Windows OS auto sets explorer.exe to run without admin as a security measure regardless of UAC and regardless of whether the User Account is set as administrator. Someone posted a link in a bugzilla bug which mentions how to force explorer.exe to work at a higher level, but how this impacts other Applications I have not checked. Here is the link:

• https://superuser.com/questions/1060456/is-there-any-way-to-run-file-explorer-as-administrator-under-windows-10/1060578

Following the instructions in this link did it! THank YOU!!

Of course my problem now is, unless I run go to the explorer.exe file location and right click>Run as admin this still all doesn't work.

What steps should i take next to have this run in admin all of the time? I already tried from the shortcut box but its greyed out as an option

bumpity