High Sierra - Mac Mail preferences reset every few days back to default.

Two other problems occur periodically every few days. In the first problem the Mailbox names shown in the sidebar mailbox list turn into a small font and become unselectable. This problem is resolved by quitting Mail and relaunching it.

In the second problem the mailbox names that appear in the Toolbar periodically change. Normally my Inbox and Sent mailboxes appear in the Toolbar but periodically these mailboxes disappear and are replaced with the Draft mailbox.

To correct this problem requires going into Customize Toolbar and reestablishing the Mailboxes that previously appeared in the toolbar.

Included is a screenshot that shows both problems, which in this case occurred simultaneously.

I followed the instructions given. It's too soon to tell if this change corrects the setting persistency problems. However, the problem of Mailbox names in the sidebar mailbox list appearing in a small font and being unselectable occurred immediately. However, quitting and relaunching Mail no longer corrects this problem. A screenshot follows.

Trashing the Mail container did not resolve the problem. The setting persistency problem has already reoccurred.

In the Favorites Toolbar the mailbox "Drafts" now appears along with the Favorites that were previously set(Inbox, Sent). Also, the sidebar Mailbox list problem still persists. Screenshot follows.

Well it happened to me with Numbers. I trashed the container files and the problem has not returned yet. But it may at some point.

For the favorites bar, you don't Customize the toolbar. Drag the mailboxes you want on the Favorites Bar.

You might also try trashing the com.apple.mail.savedState folder. Be sure to quit Mail before doing any of the steps I gave.

~/Library/Saved Application State/com.apple.mail.savedState

If you really wish to see if it's a user account problem or and OS problem, create a new user account for testing. Log into it and create your mail accounts there and test. If it works there, then there is a corrupt file in your account you will have to find.

If not, you may have to reinstall the OS. Do that with the full installer from the App Store.

If the reinstall doesn't work, send Apple feedback on the OS.

Product Feedback - Apple

Since the 10.13.1 update I am having the exact same issues with Mac Mail as p4nch. Every few days some preferences seem to reset back to their default value and I have to change them back to what they were previously.

Unfortunately I don't have a cure fot it.

Try this and see if the settings hold afterwards:

Remove Container file Mail:

Quit Mail.

In the Finder, select Go, then Go to Folder. Copy and paste the path below and hit GO:

~/Library/Containers/com.apple.mail

Move the whole com.apple.mail folder to the Trash, and open Mail and test. If all goes well, you can empty the trash. You may need to re create your user settings.

If there is a problem or you wish to restore the old file, first, Quit Mail.

Then open the Trash. Right click on the folder and choose Put Back from the menu.

Yes I realized too late that I confused the method of modifying the Favorites bar with modifying the Toolbar but you can't go back and edit posts.

~/Library/Saved Application State/com.apple.mail.savedState is an alias for a folder residing in

~/Library/Containers/com.apple.mail

so it would have been trashed in the previous suggestion you provided. Yes?

A list of all folders or files that have something to do with user settings:

~/Library/Containers/com.apple.mail :Note that there may be more than one folder beginning with com.apple.mail in Containers. You can move all to the trash and also the ones below.

~/Library/Saved Application State/com.apple.mail.savedState

~/Library/Preferences/com.apple.mail

Those are all in different locations. If you don't know how to follow the pathname, click on the desktop and in the Finder menu, select Go, then Go to Folder. You can copy and paste the path in the window and hit Go. A finder window will open to the location.

Be sure to quit Mail before doing any of this. You can restart the computer after deleting the files, but it probably is necessary.

As other have said, this has not worked for them. It may just be an OS problem.

That file hasn't been used recently by Apple within the preference folder and shouldn't have existed. I have one now which was created on Nov. 8. Are you running the latest version of the OS?

If it doesn't exist, don't worry about it. It will be run in the container folder.

High Sierra mail bugs:

1) Mail reset all settings randomly without any reasons. Never happen in 12 years using Mac!

2) replying to a message the page slip in 2 and it is too small to read, write and check That is useful if you have a 27 inch screen not a 13 or 15''!!!!

3) after replying the messages the columns width of the previous viewer window are resetting....WHY?

puzzled here!⚠

No it doesn't recreate it in the Preference folder. I also trashed mine. The actual file Mail is using was in the Container folder. It has been that way since Sierra.

I don't know why it was recreated in the preference folder Nov. 8 to begin with. I didn't install anything on that date that would have created it there. Checking my TM backups, it did not exist in the Preference folder before the 8th. Strange.

If it doesn't fix it, I would leave feedback and see if Apple provides a fix on the next update.

Let us know one way or the other.

It doesn't matter how you get the update. Software Updates in the app store provides just updates to the OS and only replaces changed or new files. If you download High Sierra from the app store, you will get the full installer which will replace the files. If an update isn't working right, sometimes the full installer will correct problems.

Exactly the same since 10.13.1, and not solved with 10.13.2. Fresh format since 10.13.1.

I tried to use AppCleaner to delete all preferences and files exept Mail.app, and the issue is still happening.

I use Mail a lot, can't figure out what did this, it happens maybe every 3-4 days.

Yes me too. I have mine set to never permanently delete from trash folder- it changes to permanently delete after 30 days. I never sort by conversation and the software is always changing that to default to organize by thread. This bug just caused me to loose 2 years of saved mail. ******.

Using OSX 10.13.3 but Apple Mail constantly changes my Sort By preferences. I set Sort By to "oldest message on top" but after logging out and then back in to Mail my preference changes back to "newest message on top".