When I send invoices or estimates via batches, many of my customers are responding that they cannot open the file. It is showing up as a winmail.dat file when they receive, but it shows pdf when I send it. How can I fix this?

Thanks for reaching the Community space, @Jersey.

I appreciate you for sending a screenshot of your concern. To fix this, let's make sure to update your QBDT with the latest release. Updating the software so you always have the latest features and fixes. I'll show you how:

1. In QuickBooks, click Help at the top. 
2. Select Update QuickBooks, then choose Update Now. 
3. Hit Reset Update and click Get Updates. 
4. When the download finishes, restart QuickBooks. 
5. When prompted, accept the option to install the new release.  

Once done, run the QuickBooks PDF & Print Repair Tool on the affected computers. This fixes issues with emailing a PDF form.

Here's how:

1. Close QuickBooks.
2. Download the QuickBooks Tool Hub file, then save it.
3. Open the file you just downloaded (QuickBooksToolHub.exe).
4. Follow the steps to install, then agree with the terms and conditions.
5. After installing, double-click the icon on the Desktop to open the tool hub.

Then, run the QuickBooks PDF & Print Repair Tool. Here's how:

1. In the QuickBooks Tools Hub, click Program Problems.
2. Select the QuickBooks PDF & Print Repair Tool. It will take about a minute to run.

After performing the steps, try to send invoices and estimates again.

You can follow the remaining process in this article: Troubleshoot PDF and Print problems with QuickBooks Desktop.

I've included these articles to know more about how to customize email templates and use them to send messages from QuickBooks:

• Customize email templates in QuickBooks.
• Use and customize form templates

You can always get back to me if you have any other questions about QuickBooks. I'm here to answer it for you. Have a great day!

I am having this same problem a year later. Anytime i send mass invoice emails through quickbooks "send forms". All my recipients complain the same. They are getting a winmail.dat file. I have already done all the recommended setting changes through outlook. They are already on the setting for HTML or plain text when using the outlook program. This is a quickbooks problem. I am tired of reading how its outlooks problem. When i use the outlook program no one has a problem, but when i use the ''Send Forms" for my invoices of customers this is what happens everytime. I have even changed my preferences for send forms and checked the use "plain text" format for emailed invoices and they still are getting it.

Hi there, @Peachjo122.

I understand that not all email services can read the winmail.dat file. I'm here to help you fix this.

This usually happens when sending emails via Outlook. Choosing either HTML or plain text in Outlook can prevent it from attaching a Winmail.dat file. You can also configure the same message format in QuickBooks. 

Here's how:

1. Go to the Edit menu and choose Preferences.
2. Select Send Forms from the menu.
3. Under My Preferences, make sure the Use "Plain Text" format for e-mailed invoices is checked. 
4. Click OK.

Alternatively, you'll want to set up and use another email other than Outlook. 

If you're getting the same issue, I suggest contacting our Customer Care Support team. This way, they can take note of your case and raise a ticket for further investigation if needed.

Furthermore, here are some resources that I'm sure you'll find helpful when you encounter issues with sending forms:

• Fix Webmail Password Issues 
• How to Fix "Error: QuickBooks is Unable to Send Your Email to Outlook"

Please come back and post about your results after following the recommended steps above. It's my priority that you find the success you need.