If Send Individually reports that a campaign was sent but the messages remain in the Outlook Outbox, the add-in may have finished its work. In some classic Outlook setups, especially IMAP or SMTP accounts, Outlook places the messages in the Outbox but does not flush the queue until Outlook starts a send and receive cycle.
That distinction matters. Reinstalling the add-in is not always the first fix. Start by checking Outlook’s send settings and the state of the messages in the Outbox.
Why Send Individually messages can wait in the Outbox
Send Individually creates a separate message for each recipient. That is the reason each person receives a private copy addressed only to them instead of seeing a shared list in To or CC. The add-in prepares those messages and places them in Outlook’s outgoing queue.
Sending then depends on Outlook’s mail transport. With some IMAP or SMTP accounts, the queue may not be flushed immediately. The messages can remain in the Outbox until Outlook performs a normal send and receive, such as when you send another message or press F9.
This is different from a campaign that never generated messages, and it is also different from a message blocked by an invalid recipient or an attachment problem. First determine which stage is stuck.
Use this four-step Outbox check
1. Check whether the messages are still queued
Open the Outbox and look at the campaign messages. Messages waiting to be sent normally appear in italics. Avoid opening a queued message while troubleshooting. Opening it can remove it from the send queue, leaving it in the Outbox until you click Send again.
If a message is not italic, open it and click Send to place it back in the queue. Then leave the Outbox and continue with the send settings below.
2. Turn on Send immediately when connected
In classic Outlook, go to File > Options > Advanced. Scroll to the Send and receive section and select Send immediately when connected.
Microsoft describes this setting as the control that sends messages composed while Outlook is offline as soon as Outlook is connected again. It is a useful baseline for an account that is leaving outgoing messages in the queue. See Microsoft’s advanced Outlook options for the current setting name and location.
3. Confirm that your account sends in its group
Press Ctrl+Alt+S to open Send/Receive Groups. Select All Accounts, choose Edit, and select the account used by the campaign. Confirm that Send mail items is checked.
Back in the Send/Receive Groups window, confirm that Schedule an automatic send/receive every is selected. A five-minute interval is a practical starting point for testing. Microsoft’s send and receive settings guide explains how classic Outlook uses groups and scheduled cycles.
4. Run Send/Receive and watch the result
Press F9, or select Send/Receive All Folders on the Send/Receive tab. Watch the Outbox while the cycle runs. If the campaign messages leave the queue, the add-in generated the messages correctly and Outlook’s outgoing transport was the part that needed attention.
After the queue clears, send a small test campaign to addresses you control. Check the recipient, subject, attachment, and delivery time before using the workflow for a larger mailing.
What to check if the queue still does not clear
If the messages remain in the Outbox after a manual send and receive, check the surrounding Outlook environment before rebuilding the campaign.
- Make sure Outlook is not in Work Offline mode.
- Check whether an antivirus or email-scanning feature is holding outgoing messages.
- Confirm that you are testing the same mailbox and account selected in the Send/Receive group.
- Do not open queued messages unless you intend to click Send again.
- Save the Send Individually log and note whether a normal email also remains in the Outbox.
If a normal email sends but the campaign does not, record the exact error text and the account type. That information helps support distinguish an Outlook transport issue from a campaign-specific problem.
When a reset or reinstall is appropriate
A reset may be reasonable when an interrupted campaign window or stale configuration is preventing a clean restart. Close current campaign windows, use the add-in’s Reset control, and start a new campaign from the main Outlook window.
A clean reinstall should be a later step, not the default response to every Outbox delay. Reinstalling does not change an IMAP or SMTP account’s Send/Receive configuration. If you do need to reinstall, close Outlook first, remove the Sperry Software add-in, install the correct Outlook bitness, and restart Outlook before testing again.
For the documented IMAP and SMTP case, the Sperry Software Outbox troubleshooting article lists the settings and checks in one place.
The practical takeaway
When Send Individually messages stay in the Outlook Outbox, separate the add-in’s job from Outlook’s job. The add-in can create the individual messages correctly while Outlook waits to flush the outgoing queue.
Check the message state, enable Send immediately when connected, confirm the account’s Send/Receive group, and press F9. Test with a small campaign before escalating. This sequence targets the mechanism that is actually stuck and avoids an unnecessary reinstall.
See how Send Individually for Outlook sends one message per recipient.
