Troubleshooting

Table of Contents Messages don’t send or send multiple times Are you using the add-on correctly? Messages not being sent: isolating the problem Test #1 Test #2 Test #3 Test #4 Test #5 Corrupt Outbox folder Corrupt Drafts folders Full temporary directory on Windows Send errors with Gmail when Thunderbird is configured to save copies Debug logging

Messages don’t send or send multiple times

Are you using the add-on correctly?

If scheduled messages get moved into your Outbox (underneath Local Folders) at the scheduled send time but don’t get delivered from there, then the first thing to do is confirm that you haven’t told Send Later not to deliver messages. Open Send Later’s preferences (click “Send Later” at the bottom of the main window and select “Send Later preferences” from the menu) and make sure the box next to “Trigger unsent message delivery from Outbox” is checked. It is checked by default, so if it isn’t, then you unchecked it for some reason, and you should check it and click “OK” to save the change. Then, to cause past messages that were previously put into the Outbox to be delivered, select the File > Send Unsent Messages menu command. If that’s not the problem, then read on.

Another common mistake when using the add-on is clicking on the “Put in Outbox” button rather than the “Send at …” button.

If you instead click the ’Put in Outbox" button below it, then you’re not scheduling the message for later delivery, you’re putting it directly into the Outbox to be sent the next time you do File > Send Unsent Messages or the next time Send Later delivers a separate scheduled message, since every time Send Later delivers a message, all pending messages in the Outbox are delivered.

Make sure you are using the add-on properly and its preferences are set correctly before proceeding with the following troubleshooting steps.

If scheduled messages are going into your Drafts folder but not moving into your Outbox at the scheduled time, then check if your mail server is discarding the Send Later headers, as described above. If not, then proceed with the following troubleshooting steps.

Messages not being sent: isolating the problem

If Send Later fails to deliver messages at the scheduled time, or if scheduled messages are delivered repeatedly, the two most likely causes are corrupt Drafts folders and a corrupted Outbox folder. A corrupted Outbox may even cause Thunderbird to crash when it tries to deliver scheduled messages. Note that corrupted folders are not Send Later’s fault… There are bugs in other parts of Thunderbird, which can cause folders to become corrupted.

If your messages aren’t being delivered properly, then please perform the following two diagnostic tests to isolate exactly where the problem lies:

Test #1

1. Disable the Send Later add-on.
2. Restart Thunderbird.
3. Compose a new message with a valid recipient, Subject, and message body.
4. Select the “Send Later” command on the “File” menu of the composition window.

If you get an error at this point, then Send Later is not the problem. Rather, one of the following is wrong:

• corrupt Outbox folder — see below for how to repair it;
• full Windows temporary directory — see below for how to repair it;
• your hard disk is full; or
• something is broken in your Thunderbird profile. This can happen for various reasons. Unfortunately the only reliable way to resolve this is to migrate to a new Thunderbird profile and get rid of the old one.
  • Note: A potentially quicker option is described here, but only attempt it if you're comfortable modifying Thunderbird's internal configuration parameters.

Test #2

1. Start with a successful Test #1, above.
2. Check the “Outbox” folder underneath “Local Folders” and confirm that the message you composed is there.
3. Select the File > Send Unsent Messages command and confirm that the message in your Outbox folder is sent successfully.

If the “Send Unsent Messages” command is grayed out in the menu, i.e., you cannot execute it even though there is a message in the Outbox, or if the message does not send successfully when you execute this command, then Send Later is not the problem. Rather, one of the problems and solutions listed above in “Test #1” applies.

Test #3

1. Start with successful Tests #1 and #2 above.
2. Re-enable the Send Later add-on and restart Thunderbird.
3. Compose a new message with a valid recipient, Subject, and message body.
4. Schedule the message with Send Later to be sent five minutes in the future.
5. Confirm that the message is saved to your Drafts folder.

If, instead of the message being saved into the Drafts folder, you get an error, then try repairing your Drafts folder and then repeat this test. If that doesn’t fix the problem, then the error you’re getting probably isn’t a Send Later issue, it’s a generic Thunderbird issue, but if you can’t figure out what the problem is, feel free to send us the error message you’re getting and we’ll try to help.

Test #4

1. Start with a successful Test #3, above.
2. Enable the “Send Later” column in the message list in your Drafts folder, if it isn’t already displayed.
3. Make sure that the Draft you scheduled shows the correct scheduled send time in the Send Later column. If it doesn’t, then you are probably running into this issue, and you need to use the workaround documented there — configure Thunderbird to save Drafts locally rather than on the mail server — to be able to use Send Later.

Test #5

1. Start with a successful Test #4, above.
2. Wait for the scheduled send time of the message and confirm that it is sent correctly by Send Later.
3. If it isn’t, and all the other tests above were successful, then contact us for further assistance.

Corrupt Outbox folder

If your messages aren’t being delivered or are being delivered multiple times, then the first thing you should try is clearing your Outbox. Here’s how to do that:

1. Make sure the “Outbox” folder under “Local Folders” doesn’t have any messages in it (because we’re about to delete the folder). If it does, and you want to save them, move them into your Drafts folder to be resent later.
2. Right-click (on Mac, perhaps ctrl-click) on “Local Folders” and select “Settings…”.
3. Note the directory in which your local folders are stored.
4. Browse to that directory.
5. Exit completely from Thunderbird.
6. Delete Outbox and Outbox.msf in the Local Folders directory if they exist. Also delete “Unsent Messages” and “Unsent Messages.msf” if they exist. If neither of them exists, then you’ll have to use the advanced configuration editor in Thunderbird and look at the setting mail.default_sendlater_uri to find out the name of your Outbox folder on disk and then delete it (after exiting again from Thunderbird).
7. Try scheduling a message with Send Later again and see if the problem is gone.

Corrupt Drafts folders

A good sign that one of your Drafts folders is corrupted is if Send Later isn’t noticing that there are scheduled messages, i.e., the message at the bottom of your Thunderbird window says “IDLE” instead of “PEND 1”, “PEND 2”, etc. However, if messages aren’t getting sent at the scheduled time, then you may still have a corrupted Drafts folder even if the message says “PEND”.

1. Locate the Drafts folders for all of your accounts. The easiest way to do that, if you have multiple accounts, is to switch to the unified folder view (View > Folders > Unified) and expand “Drafts”.
2. Right click on each one and select “Properties…”.
3. Click the “Repair Folder” button in each Properties window, then click “OK”.

NOTE: Repairing a folder resets its visible columns, column layout, and sorting, so if you’ve customized the columns and/or sorting, you’ll have to put the customizations back after repairing the folders.

Full temporary directory on Windows

If your Windows temporary directory ends up with too many files in it, which is partially Thunderbird’s fault since it has a habit of creating temporary files and not deleting them, then both Send Later and Thunderbird may start malfunctioning. The two surefire signs of this are, (a) Send Later is able to copy messages into your Outbox for delivery, but once they’re there, Thunderbird fails to deliver them, and (b) when there are messages in your Outbox, the File > Send Unsent Messages command doesn’t work, or is greyed out and can’t even be selected. If you this you may be running into this problem, you should run the Windows Disk Cleanup utility and tell it to clean up temporary files.

Send errors with Gmail when Thunderbird is configured to save copies

Many users of Send Later report errors when the add-on attempts to send scheduled messages through a Gmail account. These errors happen more often, but not only, when Send Later attempts to deliver multiple messages at the same time. This is usually caused by an error in the Thunderbird configuration for the Gmail account. In particular, it is not necessary to configure Thunderbird to save copies of sent messages in Gmail’s Sent Mail folder, since Gmail saves copies there automatically (this is documented in Google’s configuration instructions for Thunderbird). When Thunderbird is incorrectly configured to save copies, it can cause message delivery errors. When this occurs, the delivery error happens after the message is sent to its recipients, when the copy is being saved in Sent Mail. This could potentially cause the recipients to receive multiple copies of the message, since if the user then tells Thunderbird to try sending it again, it might re-attempt the entire delivery, not just the saving in Sent Mail. Therefore, if you are experiencing errors with Send Later through a Gmail account, check your account settings to see if you have “Place a copy in” checked in the “Copies & Folders” settings, and if so, turn it off.

Debug logging

If you ask us for help with a problem you are having with the add-on that we can’t reproduce ourselves, then we may ask you to enable debug logging on the add-on, perform some task with debug logging enabled, and then send us the resulting debug log. Here are the instructions for how to do that.

1. Click on “Send Later” at the bottom of the main Thunderbird window and select “Send Later Preferences”.
2. Change “Console log level” to “All” (or whatever other value I tell you to change it to).
3. In the main Thunderbird window, type Ctrl-Shift-J to open the error console.
4. Click the little trash can icon in the upper corner to clear the window.
5. Do whatever task I told you to do with debug logging enabled.
6. Repeat steps 1 and 2 above, but this time change the setting to “Fatal” or “Info” instead of “All”.
7. Right click on one of the messages in the error console window and click “Select All”.
8. Copy and paste the selected messages into an email message to us.