I think this "network connection failure" is due to me having desktop pro 2020 and no subscription. Service expired 5/31, but I didn't expect emailing to be excluded. That was never listed in all the info we all received and were warned about. 

We also had this problem. CS had us go into Edit, Preferences, Send Forms. Instead of Web Mail, check Quickbooks email. This worked for us. They said that on June 16 an update will address this and we can go back to Web Mail. Hope this helps.

I had a problem with error popping up for every computer at our office for sending out estimates or invoices (We have Gmail webmail). It started popping up randomly a few weeks before, but we just pushed the send button again, and it would send. Now though every time it happens.

I got it to work now, here is my fix:

For the Web Mail, select Other instead of Gmail.

Put in the stmp.gmail.com, 587, check box respectively. (Like PBWCPC says)

In Gmail, make sure you have IMAP enabled.

Make sure "Less Secure Apps" is enabled from your google account (This is what fixed it for me)

Then next time you send an email from QB, it will ask you to for your password. It worked for a couple computers in our office.

(Now I am having problem on another computer where it can't access the email server, but that is a separate company/email domain...not sure why though

Shout out to PBWCPC for pointing me to the right direction

Same problem with QB Desktop 2021 Pro. I wasted 2 or 3 hours trying to figure out "network connection failure" before landing on this page and finding out you all know about the problem and haven't corrected it. How will we know the problem is fixed? I only send out batch statements once a month and finding out on the day of sucks.

I don't think it is QB's fault. Its probably because google changed something, and QB didn't have time to make a fix for it. My guess, QB will make put an update out to change how the Gmail Webmail or at least put a guide out on how to set google's "Less Secure App" to on.

Hi, @WV-CPA. I appreciate your feedback.

Yes, we have an open investigation about QuickBooks being unable to send emails due to network connection failure when sending batch emails using a Gmail account. Please follow the steps that are shared in the previous response on how to reach out to our QuickBooks Support Team so they can add you to the list of affected users. 

As of now, we don't have an exact time frame for when this will be fixed. Rest assured that our engineers are already working on a permanent resolution to address the issue. You will also be notified as soon as we get this working. 

While we work to find a fix for this, I have a workaround that you may find helpful for the time being. You can send invoices of three or fewer and use a different webmail provider like Yahoo or outlook.com. You may also use another method like Outlook or QuickBooks Email service if available. For more information about connecting your email, see this article: Connect your email to QuickBooks Desktop.

Feel free to check out these articles in case you will be needing them in your future tasks in QuickBooks:
 

• Get started with customer transaction workflows in QuickBooks Desktop
• Use and customize form templates

Don't hesitate to reply to let me know if need anything else when working in QuickBooks. I'll jump right back and offer my help to you again. Take care.

Having exactly the same issues.

But additional note - I am now being notified that the emailed invoices that Quickbooks does send is going to the Spam folder???

Hi there, @CoolMonroe.

I can see the urgency of being able to email invoices to your customers. I checked the status of the investigation about QuickBooks being unable to send emails due to network connection failure, and it's still in progress. 

I know it's been a while, but rest assured our engineering team are doing their best to get you back on track as soon as possible. If you haven't contacted our Customer Care Team, I suggest getting in touch with them so that you can be added to our notification list.

To reach them, here's how:

1. On your QuickBooks account, go to the Help menu at the top.
2. Select QuickBooks Desktop Help. 
3. Choose Contact Us. 
4. Enter the issue or topic in the field box. 
5. Follow the onscreen instructions.

You can also check out this link for more information on contacting them: Contact QuickBooks Desktop support. Ensure to review their support hours to know when agents are available.

In addition, if you change your way of sending emails, I recommend having your clients check their filter settings and ensure that those emails are not being routed to spam.

Please let me know if there is anything else I can do for you by leaving a comment below. I'm here to lend a hand. Have a wonderful day!

We've had to switch to Thunderbird to use for QuickBooks. It's a bit annoying, but it works. I just hope they fix the problem soon so I can switch back!

Any word on a fix for this yet? It's been two weeks. We are currently utilizing the workaround of using Gmail's SMTP server (thank you!) but it's much slower than the usual webmail way. We are extremely worried that this will still be an issue when we will have thousands to send out this summer...

It isn't the kind of experience I want you to have while sending emails from QuickBooks Desktop (QBDT), Jeff. Let me share some information about this issue.

I want you to know that the investigation mentioned in the previous replies was already closed and resolved. Since you've experienced the same issue, I recommend you perform some basic troubleshooting steps to narrow down the result.

First, update QuickBooks to the latest release to get the latest features and fix common errors right away. To start:

1. Go to the Help menu, then Update QuickBooks Desktop.
2. Select Update Now, then select Get Updates.
3. When finished, close and reopen QuickBooks. 
4. Hit Yes when asked to install the update.
5. Follow the onscreen instructions to complete.

I'm also adding this article for more reference: Update QuickBooks Desktop to the latest release.

You may also check out the solutions from this article to fix error messages while sending emails from our system: How to fix "Error: QuickBooks is unable to send your email to Outlook".

If you have follow-up questions, let me know by leaving a comment below. I'm pleased to help you again. Keep safe!

I understand how frustrating it can be when you're unable to send email invoices to your customers, WizAccounting. 

The investigation regarding this issue has already been closed. Since you are still facing the same problem, let's ensure updating QuickBooks to the most recent release. By updating, you can stay up-to-date with the latest improvements and bug fixes available. 

After updating QuickBooks, try removing and then re-adding the email address. This process can help refresh the email settings and resolve any potential issues that may have been causing errors while sending emails. 

If the issue continues, I suggest contacting our QuickBooks Desktop Support team for further assistance. They have the necessary tools to access your account and thoroughly investigate this matter. 

For now, you may consider sending your emails outside of QuickBooks Online as an alternative solution.

In addition, you can also check out this article for potential solutions to address any error messages you encounter when attempting to send emails. This provides helpful information that may assist you in resolving the issue: How to fix "Error: QuickBooks is unable to send your email to Outlook".

The Community is always here to lend hand if you need further help.

This happen if have multiples in CC: destination CC: .  If have one emails sent successfully

If you have multiple people in the send to boxes, put a semi colon between the names instead of a comma.

That resolved my issue/