I understand this also exists in 26.

It gives an error or if it attacks it ends up being corrupted. QB for example will create an email, but not attach a file.

Anyone figure out a fix or workaround.

Not sure if this setting would help:


Otherwise I haven't had issues with attachments in the Mail app.

Sorry no help. This is beyond frustrating as I have print deadline and need to send proofs back a forth. Be damned if do update right when they come out anymore after this crap.

What is the best email client out there?

After deleting some preference files, Mail was allowing me to attach files and then this morning it won't allow me to attach files again. I changed nothing. This is a total mess.

Possibly a conflict with Quickbooks that gets this started.

Deleting this one preference file "com.apple.mail.plist" fixes it. But how long that will last who knows and what is causing it to become corrupted.

Here is the path to that file /Users/~/Library/Containers/com.apple.mail/Data/Library/Preferences

Back again so now deleting "com.apple.mail.plist" does not fix it.. I went to download 26.0.1 to start a clean install on a new partition (Volumn) and it did not stop and ask and went ahead and up dated without my permission. That is BS.

Anyway I am now running 26.0.1 and had no problems with mail for over a week then suddenly it is back. Last time I sent an attachment was on the 24th. Nothing changed since then. Needless to say I am highly pissed at this.

Do you have a webmail interface to your account? Doesn't fix your problem with Mail but it might let you get your file(s) out.

FWIW, I use Thunderbird as my default mail client. I keep Mail open for Spotlight indexing and for the occasional time when I want to create an email from a file I want to send as an attachment (drag file to Mail icon).

I see an option in Thunderbird to import data from Apple Mail but I have not tried it.

If you are looking to create a mail message with an attachmentfrom another program like Quickbooks, such as "Send document as an email attachment," Thunderbird may or may not help. Even though I have it as my Default Mail client, some integrations don't work. e.g. it doesn't show up as an option in Share sheets and such.

I found another strange thing just now. I can attach files if they are in the Documents or Downloads folder. Trying to figure out why that is. And what cause that to change between last night and today.

That is strange, indeed. I am also on Sequoia 15.7.1 and I am able to attach and send from any folder with the Apple Mail client.

Doing some testing with another folder in my user directory set to the same permission as Documents or Downloads folder and with a copy of the same file in the that is in the documents folder. It won't attach if it from the new folder.

I just discover that PDF file inside of a folder in the Applications folder will attach, but a file in the Users folder will not attach.

Very odd. Do you have multiple email addresses set up? If so, does this happen on those other accounts?

Mail does have a Mailbox->Synchronize option to rebuild one or all accounts. That fixed a Mail glitch I had a couple of years ago with an older Mac but that had nothing to do with the issue you're facing.

Of course, if you have a deadline and a working solution, I'd say go with that until the deadline has passed!

Testing here with an open New Message window. I have files attached that came from the Documents, Downloads or Applications folder. But trying to attach files from any other folder will not work or trying to create an email from QB or LR for example will not attach the files even though it will open a New Message window.

When I try to drag and drop where the attachment will just say download if I highlight it and hit the space bar this is the message I get.

"Mail was unable to save the attachment “07235715.zip” to disk. Verify that your downloads folder exists and is writable."

Not sure what GB or LR are. WAG: Any chance this is an iCloud issue? I don't use iCloud myself but know that there are settings that will store files on the cloud to save local disk space.

Should be Quickbook and Lightroom. No Mail is not stored on the cloud.

I was wondering if the working source folders were on iCloud/Local and the nonworking ones were on Local/iCloud.

I just realized you are now on Tahoe (missed some of your earlier posts.) It sounds like Synching Mailboxes may be worth a try but not if you are still under deadline pressure.

26.1 seems to have fixed this problem, or was it just the reboot? Hope it lasts but this problem has been so strange that I would not be surprised if it comes back.