If your QuickBooks invoice is not sending, the problem can prevent customers from receiving invoices, payment links, estimates, or other sales forms. You may click Send in QuickBooks, but the invoice may remain unsent, show as undeliverable, or appear to send without reaching the customer.
In QuickBooks Online, invoice-delivery problems can be related to incorrect customer or company email addresses, spam filters, email-server configuration, or connected Gmail authorization. In QuickBooks Desktop, email-server configuration and outdated software can also cause sending errors. Intuit has published updated troubleshooting guidance for these issues in 2026.
This guide explains the common causes of QuickBooks Invoice Not Sending 1-888-394-9989 and the practical steps you can take to fix the problem.
You may experience symptoms such as:
There isn't always one single cause. The problem can originate from the customer email address, your company email settings, your connected email provider, or QuickBooks itself.
An incorrect or outdated customer email address is one of the first things to check.
Even a small typo can cause an invoice to bounce or become undeliverable.
Check for:
Intuit's current troubleshooting guidance recommends checking the customer's email address and correcting it before resending the invoice.
Your company-facing email address can also affect QuickBooks email delivery.
In QuickBooks Online, check the email address under your company settings and make sure it is correctly formatted.
Intuit specifically recommends clearing and re-entering the company email address if customers aren't receiving QuickBooks emails.
Sometimes QuickBooks successfully sends the invoice, but the customer's email provider places it in:
Ask the customer to search their mailbox for the invoice before assuming that QuickBooks failed to send it.
Intuit recommends checking junk and spam folders when customers don't receive invoices.
If you're using Gmail to send QuickBooks Online invoices, the Gmail connection may need to be authorized correctly.
QuickBooks currently allows users to connect a Gmail address and requires the appropriate permission to send email on the user's behalf. If delivery problems occur, Intuit recommends removing and reconnecting the Gmail account and granting the required permission again.
If QuickBooks emails are being blocked by your company's mail server, customers may not receive invoices even when the QuickBooks invoice itself appears correct.
Intuit recommends having an IT professional configure the email server to accept the QuickBooks Online mail-server host names and IP addresses when the standard troubleshooting steps don't resolve delivery problems.
Try the following solutions in order.
Before resending an invoice, check its current status.
In QuickBooks Online, go to:
All apps → Sales & Get Paid → Invoices
Look at the Status column.
An invoice may show as:
Intuit recommends checking the invoice status first when an invoice isn't reaching the customer.
Open the affected customer's profile and confirm the email address.
Check carefully for:
Correct the address and save the customer information.
Then resend the invoice.
In QuickBooks Online:
If the email address appears correct but QuickBooks emails still aren't being received, Intuit recommends clearing the field and entering the address again without extra spaces or characters.
After correcting the email address, send a test transaction to your own email.
This can help determine whether the problem is:
If the test email arrives but the customer doesn't receive their invoice, investigate the customer's email address and spam filters.
If the invoice status says Sent, ask the customer to check:
The customer should also search for the invoice using your company name or invoice number.
If you're sending invoices through a connected Gmail account and email delivery has stopped:
Intuit's current instructions specifically recommend removing and re-adding Gmail when email delivery problems occur.
Gmail-specific problems can occur after account or authorization changes.
If your QuickBooks invoice isn't sending through Gmail:
Open the invoice.
Select the email sender/From option.
Review the connected Gmail account.
If necessary, remove the Gmail connection.
Connect Gmail again.
When prompted, allow QuickBooks to send email on your behalf.
Send a test invoice.
Intuit currently states that only one Gmail address can be connected to the QuickBooks Online account for this sending method.
If the invoice status is Undeliverable, check the recipient's email address first.
QuickBooks may identify an invoice as undeliverable when an email bounces or the recipient's email server has a temporary problem.
You can also check the task manager for email delivery errors when available.
If QuickBooks shows the invoice as Sent, the invoice may have left QuickBooks successfully but been filtered or rejected by the recipient's email system.
Ask the customer to:
If several customers are experiencing the same issue, investigate your company email configuration instead of troubleshooting each customer individually.
QuickBooks Online can display a Delivery Server Down error when sending sales forms or invoices.
Intuit's current guidance says this error can be related to invoice attachments or company email configuration. Suggested checks include:
Make sure the company and customer-facing email fields contain properly formatted email addresses.
For example, an address should look like:
rather than including labels or prefixes inside the email field.
Intuit specifically identifies improperly formatted email addresses as a possible cause of Delivery Server Down errors.
QuickBooks Desktop uses different email configurations than QuickBooks Online.
If QuickBooks Desktop cannot send an invoice, check:
Intuit currently documents a "Couldn't Connect to Email Server" problem in QuickBooks Desktop, including cases involving Yahoo email accounts. One recommended solution is updating QuickBooks Desktop to the latest release.
If you're using QuickBooks Desktop:
Keeping QuickBooks updated can resolve compatibility problems involving email services.
If you receive an error such as:
"Couldn't Connect to Email Server"
or QuickBooks reports that it was able to connect to the remote server but couldn't understand the server response, the problem may involve your email provider or email configuration.
Intuit currently recommends troubleshooting this issue in sequence and updating QuickBooks Desktop as one of the solutions.
Check:
If the invoice itself can be created but the PDF cannot be attached or sent, the issue may involve the invoice format, PDF settings, or attachments.
For the QuickBooks Online Delivery Server Down error, Intuit specifically recommends checking invoice format and Adobe Acrobat/Reader and browser PDF settings.
Try sending the invoice without unnecessary attachments and check whether the invoice format contains unusual characters or formatting.
If you recently changed the company email address, update the email information inside QuickBooks.
A mismatch between the old email configuration and the new address can interfere with invoice delivery.
If the email appears correct but QuickBooks still isn't sending invoices, clear the company email field and manually enter the correct address again. Intuit currently recommends this approach for customers who aren't receiving QuickBooks emails.
If invoices send successfully to other customers but fail for one customer, focus on that customer's information.
Check:
If other customers receive invoices normally, the problem is less likely to be a general QuickBooks email-delivery outage.
If several customers aren't receiving invoices, check your company-wide email configuration.
Review:
Intuit recommends configuring your email server to accept QuickBooks Online mail-server host names and IP addresses when customer emails still aren't being delivered after the standard troubleshooting steps.
If invoice email stopped working after a QuickBooks update:
For QuickBooks Desktop email-server problems, Intuit specifically recommends ensuring the software is updated.
Never provide sensitive account information to an unofficial support provider.
Do not share:
When troubleshooting email delivery, you generally only need the invoice number, error message, email configuration details, and non-sensitive account information.
Consider contacting QuickBooks support when:
If your organization uses a managed email server, an IT administrator may need to review the mail-server configuration and allow QuickBooks email traffic.
Common causes include an incorrect customer email address, incorrect company email settings, spam filtering, Gmail authorization problems, email-server restrictions, or QuickBooks Desktop email configuration problems.
An invoice may be marked undeliverable when the recipient's email address is incorrect or the recipient's email server temporarily rejects the message. Check the customer's email address and resend the invoice.
First verify the customer's email address and ask them to check their spam and junk folders. If multiple customers aren't receiving invoices, investigate your company email configuration.
The Gmail connection may need to be reauthorized. Remove and reconnect the Gmail account and make sure you grant QuickBooks permission to send email on your behalf.
The Delivery Server Down error can be associated with invoice attachments, email-address configuration, invoice formatting, or PDF-related settings.
Update QuickBooks Desktop, review your email-provider settings, verify your webmail or Outlook configuration, and check whether QuickBooks can connect to the email server.
If only one or a few customers are affected, check their email addresses and spam filters. If nearly every customer is affected, investigate your company email configuration or QuickBooks email service.
Yes. First correct the email address or delivery problem and verify that the invoice wasn't already successfully delivered or paid. Then resend it from the invoice screen.
When QuickBooks Invoice Not Sending, start by checking the invoice status, customer email address, company email address, and spam/junk folders. If you're using Gmail, verify that QuickBooks has permission to send email on your behalf and reconnect Gmail if necessary.
For QuickBooks Desktop, email-server configuration, webmail settings, and outdated software can contribute to invoice-email problems. Updating QuickBooks and reviewing the email-server connection can help resolve these issues.
If multiple customers are affected, don't assume every customer has an email problem. Check your company-wide email configuration and QuickBooks Payments/invoicing environment first.
