It would be best to address the main problem, which is that the "Show remote content in this message" option is not working. There is a reason why we want remote content blocked sometimes, and that is to protect against harmful code associated with remote content.

Plus I don't know a good way to fix your problem with permissions.default.image

1. Run a Check Disk to fix any file system errors. How to run a "Check Disk" in Windows

2. Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled".

If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.

3. Restart the operating system (Windows or OSX), in Safe Mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, OSX.

Then see if Thunderbird works better. If it does, then another program or process is interfering with Thunderbird when Windows is running normally. Likely your anti-virus.

If the above doesn't help, then we will move on to uninstalling Thunderbird then installing it again, and/or creating a new Thunderbird Profile.

Thanks, Bruce. I followed all of your suggestions, but no luck.

In each case I took the steps you suggested, then opened Thunderbird. I opened the email version of your reply to my post (which has remote content, and for which I had previously selected "Show remote content in this message"). The remote content did not display. I then opened the config editor, confirmed that the value of permissions.default.image had changed from my previous setting of 1 to 2, reset permissions.default.image vack to 1, and closed and re-opened your message. The remote content then displayed properly.

Any further suggestions will be appreciated.

Just to test, Create a new profile in Thunderbird and see if it works better. If it does, then you can transfer all your stuff from the old profile to the new one.

If a new profile does not work better, then Manually backup the Profile folder (just in case), then uninstall Thunderbird, and Download & install the latest version of Thunderbird again.

When you uninstall Thunderbird, it will leave your Profile folder behind, which contains all your e-mail and settings. Then when you install Thunderbird again, it will see the Profile folder and automatically use it.

Each time you test to see if it is working properly, try a different e-mail.

Thanks for your help, Bruce. Unfortunately, new profile, no change. Reinstall, no change.

One thing I probably should have mentioned at the outset: when I restart Thunderbird and open the config editor, in addition to the Value of permissions.default.image being 2, the Status is shown as "user set". When I Modify the Value to 1, the Status changes to "default". I'm guessing this isn't useful info, but I include it just in case.

Do you have any further suggestions?

Thanks again.

Do you have View/Message Body as set to Original HTML?

http://kb.mozillazine.org/Images_in_messages_do_not_appear

If you have a security program scanning incoming mail, that might also block remote content.

Thanks for the suggestions. Yes, Original HTML set. Also, not all images are blocked. Images included in messages show up just fine. So I doubt it's an incoming scanning issue.

Remote content is blocked by Thunderbird ("Tools>Options>Privacy>Allow remote content by default" is unchecked), so those images don't display by default. The problem is *only* with images that should be displayed by selecting the "Show remote content in this message" option in the message's "notification bar".

Those images will only display when permissions.default.image is set to Value 1 in the config editor. I can set permissions.default.image to 1 with no problem. When I do that images display as they should.

But each time I start Thunderbird (or close? don't know which), the value of permissions.default.image is set to 2 by something or other, and until I reset it to 1, supposedly-allowed remote-content images do not display.

I'm trying to figure out what that "something or other" is, and make it stop changing the value. Any suggestions will be greatly appreciated.

Changing that value for "permissions.default.image" to 1 does the same thing as selecting the option you mentioned: Menu bar: Tools: Options: Privacy: "Allow remote content in messages"

So select that option.

You seem so focused on the setting "permissions.default.image" that I believe that you have not fully uninstalled, reinstalled, and created a new profile. If you had done it properly, the original issue of "Show remote content in this message" not working, would be solved.

There is a (very) long discussion of a similar problem here. You can try the chosen solution, or do what is often faster and more effective, namely create a new profile with Profile Manager, set up your accounts, then transfer the mail and contacts from the old profile to the new one.

Hmmm. That's interesting. Not being a developer, I have no idea what "permissions.default.image" is *supposed* to do. But if it's somehow tied to the checkbox at Tools: Options: Privacy: "Allow remote content in messages", that might explain why it gets reset each time I restart Thunderbird, since I have that checkbox unchecked.

There's some dissonance here, though. Having the checkbox unchecked is the default for Thunderbird. But when I start Thunderbird and look at permissions.default.image, the value is 2 and the status is "user set". When I change the value to 1, the status changes to "default". You would think that since the checkbox is in the default state, permissions.default.image would be set to the default value. It's not.

So I just ran a small experiment. First, I checked the value - it's "2". Then I checked the check box, OKed out of Options, then went to the config editor and checked the value. Still 2. Then I unchecked the check box, OKed out of options, then checked the value. Still 2. The checkbox made no difference.

To verify, with the checkbox value set to 1, I quit and restarted Thunderbird (with checkbox unchecked). Value of permissions.default.image was 2 and user set. Checked the checkbox. Quit and restarted Thunderbird. Value of permissions.default.image was still 2 and user set. So it doesn't seem that the checkbox affects the value of permissions.default.image.

The only reason I focused on permissions.default.image is I found it in a post that recommended setting it to 1 to solve my problem. Remember, my problem isn't about *all* remote content. It's only about remote content in individual messages where I have selected "Show remote content in this message" option in the message's "notification bar".

Again, I don't know how it's supposed to function, but on my system when I change the value to 1 (the "default" value) a) remote content continues to be blocked (as would be dictated by the unchecked checkbox) for messages in general and b) when in an individual message I select "Show remote content in this message", the right thing happens. This lasts until I quit Thunderbird.

What I'm trying to accomplish is just the correct default behavior. I don't want to display remote content in all messages, for the privacy-related reasons that make this the default setting. So checking the checkbox wouldn't solve my problem, even if it worked the way you suggest.

I just uninstalled and reinstalled again and created another new profile. The situation didn't change. So I'm stuck.

Thanks sfhowes. Problem solved. I took the following steps, as suggested by the post whose link you provided:

1) Deleted "user_pref("permissions.default.image", 2);" from the prefs.js file in my default profile. (This line also appeared in each of the two test profiles I created through this process. No idea how it got there.) 2) Uninstalled Thunderbird, including reboot. 3) Moved the Mozilla Thunderbird folder from C:\Program Files (x86) to my desktop. There was lots of stuff (95 MB) still in there. 4) Reinstalled Thunderbird. 5) Started Thunderbird. Checked value of permissions.default.image. It was 1! 6) Checked operation of Options>Show remote content in message. Worked fine. 7) Repeated steps 5 and 6 a couple of times just to be sure. Worked fine each time. (One expects software to work consistently, but...)

There was some discussion of MozBackup as a cause of the problem in the post you sent. I've never used MozBackup, so I don't think that's the cause of issue.

I started using Thunderbird at v38.3.0, but after installing I reverted to v1.5.0.14. I wanted to import my email archives from Eudora, and a post in this forum suggested that for best results I should use the older version. (Import was successful.) Maybe that left some cruft around that installing later versions didn't correct, and uninstalling didn't delete. Pure speculation of course.

But since I've never used any add-ons, the problem must exist within (some version of) Thunderbird itself. I note in the post you sent that Toad-Hall submitted a bug report that was closed as RESOLVED INVALID with a lot of snippy comments about MozBackup. But MozBackup was not an issue in my case.

I also note that Matt commented "This has occurred in random profiles over a number of years. It would be good to get to the root cause so it can be fixed.". Unfortunately, I don't think that we got to a root cause, and the uninstaller seems to be a Mozilla, not a Thunderbird, problem, so I don't suppose there's any way to take this further.

Again, thanks for your help in running this to ground.

Thanks to you too, Bruce, for trying to help.

Oops. Turns out I left some stuff out in my description of the steps taken to solve my problem in my last post. Specifically, Step 1 should read:

1.1) Deleted the profile name folder called 'xxxxxxxx.default' (where the x's are letters and numbers of my default profile folder name) from C:\Users\<Windows user name>\AppData\Local\Thunderbird\Profiles.

1.2) Deleted "user_pref("permissions.default.image", 2);" from the prefs.js file in my default profile found at C:\Users\<Windows user name>\AppData\Roaming\Thunderbird\Profiles\<Profile name>\ . (This line also appeared in each of the two test profiles I created while trying to solve this problem. No idea how it got there.)

1.3) Deleted the files session.json and xulstore.json from my profile in the same location as in step 1.2.

Steps 2 through 7 in my last post are correct.

Perhaps doing Steps 1.1 through 1.3, without steps 2, 3 and 4, would have solved the problem. But I didn't do that, so I'll never know...