There are just so many files format in the computer world. Most of these formats are exclusive to some applications, like whenever we see a .xls file, we can attribute it to Microsoft Excel, a .docx is often attributed to MS Word, .jpg we know they are images and need a photo viewer app to access it and much more, but we seldom know which app is responsible for a .dat file or which program we can use to open DAT files.
So if you fall into the category of those who have little or no idea of what a .dat file is or how to open dat files on Mac, this article is perfect for you.
What is a Dat File?
First, the .dat extension stands for Data, and as we know already, data could be anything. Dat files aren’t human-generated; any program can create them on your computer. So far, they are usually created on Windows computers by Microsoft Exchange Servers.
These files come in different forms. They could be text, binary, etc. Most people have seen these files in real data for a video file for programs like CyberLink PowerDirector, VCDGear, VLC, and much more.
They all come in unique formats. Mac users often contact this file from their Windows counterparts, especially in emails they opened with the default Mac Mail app sent from Microsoft Outlook.
The most common names people encounter .Dat files are named winmail.dat or ATT0001.dat; if you met this file with any of these names, especially the winmail.dat, it is because whoever sent you the file used Windows Outlook. They didn’t purposely send this file as they can’t create it; it is, however, due to the format they sent.
You rarely encounter this file format if your sender sent the mail in the usual plain-text email body with no formatting of any sort. So if this mail contains fancy formatting like bold or italic text, background image, random fonts, signatures, logos, and the rest, there’s a chance that you might receive the file with a .dat extension.
It isn’t their fault; they may be preserving an age-long practice or using their company’s template. Asking them to turn off the formatting might be good, but if you can’t reach out to them again or can’t get them to format it in the usual plain text format, you will have to open these files. So, to open your winmail.dat file, keep reading to see how to.
How to open .dat file on Mac
We now know that winmail.dat files are often sent from Windows computers. Apple has given fair advice that you should ignore this file if it arrives via your Mail app. Sometimes, it is best to open this file, especially if you know the reason for the mail.
What often happens is this, the winmail.dat file, as we stated above, is the styled version of the mail sent from a Windows computer, so if you’ve received the mail and gotten what you need, it is pointless opening the file.
However, this winmail.dat file could be a misidentified attachment like an RTF file, Spreadsheet, MS Word document, calendar invite, etc. So, these are the ways to open .dat files on Mac.
1. Saving the file in it’s expected format
As we discussed above, most winmail.dat files are misidentified attachments. If by chance you have an idea of the file format you were expecting or somewhere in the mail you can see a “find word document attached” or something in-line with that, all you’ll need to do is resave the file to the file format you were expecting.
You’ll need to toggle on the Mac feature that shows file extensions (that is, if Mac doesn’t show file extensions, which is often a default setting).
- From your desktop, open the Finder menu and select Preferences (most Mac display this as Finder Preferences).
- Locate and click the Advanced tab (a gear icon often represents it).
- Check the Show all filename extensions box. Your file extensions should start showing, if it doesn’t, uncheck and recheck the box.
- Next, go to your Mail app and the email that has the winmail.dat
- Control + click or Right-click on the winmail.dat file and select the Save Attachment option.
- Mac then opens a dialogue box, in the text field for the file name, replace the dat file extension with the file extension you were expecting.
- Select the location you plan on saving the file and hit the Save button.
- Go to the file location, rename it to a familiar name, and then save the new name and access it.
Note, this walk-around won’t work for every .dat file. However, this will work for files whose extensions were mistaken by your device. A wrong file extension is enough to stop Mac from opening specific files.
2. By using Mac TextEdit
Another method will be to use TextEdit or any other text app. The idea behind this is, that most dat files are text-based, and an app like TextEdit should open it. Not that TextEdit will show you precisely what is in the file, it will instead give us an idea of how to open the file; we will be looking out for any clue that might point out the app it is compatible with
- Download the dat file to your device.
- Right-click on the dat file and hover over Open With.
- From the drop-down menu, select TextEdit.
If TextEdit is unable to open the file, it isn’t a text-based file. Most Dat files are inaccessible and should be left that way.
If the file eventually opens in TextEdit, go through the data there. They are often lines of codes or instructions meant for a specific program. So, if you find any familiar program name among the text there, there’s a chance that the mentioned program will open the file.
3. By using an online tool
From my computer, it’s a screenshot
If you still can’t access the file, you should try an online tool like the one in the steps below.
- Open the mail that contains the winmail.dat or ATT0001.dat file.
- Right-click on the file and select Save Attachment to have it on your Mac.
- Open your browser and visit this link.
- Click on the Choose File button; this opens a file browser window, locate the dat file.
- Double-click on the dat file or select it and click the Choose button at the window’s lower right.
- Click on the big blue Start button on the winmaildat.com page.
- Give the site some time to convert/extract the file. Locate the download button and get the converted file. If the dat file is empty, it won’t extract anything.
Winmaildat.com stores the extracted file for 30 minutes.
4. Opening with Gmail
Method four involves you forwarding the mail to your Gmail account. Or, if you received the winmail.dat file in your Gmail mailbox, you can open it from Gmail’s web-based site.
All you have to do is click the Forward button, and input your Gmail address. Then open Gmail.com on your web browser, and sign in by filling in the details required. Locate the forwarded mail. For some reason, the Gmail site can interpret the data in these emails.
Gmail will either render the file as a formatted email that it is, or you can access the attachment with Google Docs.
5. Open with a third-party tool
Another way to access winmail.dat on Mac is with a third-party app. An app called TNEF’s Enough is renowned for quickly opening this file format. If you continuously receive these types of emails, grabbing this application is the best advice.
- Visit the Apple app store and type in TNEF’s Enough into the search box or simply click this link.
- Follow the installation process.
- Select the dat file and right-click, then hover on the Open With option.
- From the drop-down menu, locate and select TNEF’s Enough. If you can’t find the app, click the Other option and search for it.
- The app then extracts the information contained in the dat file. You can then save or export the file to any location of your choice.
This app is free; it even has an iOS version. The people behind this app had this to say about the process.
TNEF’s Enough allows Macs to read and extract files from Microsoft TNEF files. The files are usually received via email from Microsoft Exchange and Microsoft Outlook users. Standard email programs will receive the TNEF file as an attachment named “winmail.dat.”
The “winmail.dat” file can contain attachments, contact files (.vcf), or calendar files (.ics), as well as a rich text or HTML version of the email body. TNEF’s Enough can open the “winmail.dat” file and allow you to extract the attachments.
6. Additional Method
You could also try reaching out to your senders and pleading they send you emails without too much formatting. This method might not work out sometimes; however, you can give it a shot.
Below are some frequently asked questions and answers to them.
1. What program opens a Dat file?
They aren’t any specific programs to open Dat files on Mac. These files are sometimes created by particular programs to be used by them only and should be left that way. However, Dat files that are text-based can be opened with apps like TextEdit or TNEF’s Enough.
2. How do you open a .dat file in Excel Mac?
Opening Dat files in Excel is only possible if you knew beforehand an excel file was to be attached to the mail. If you’ve reached out to your sender and you are sure it’s an Excel file that was misinterpreted to be a Dat file, all you have to do is
1. Open the mail on your Mac Mail app.
2. Right-click on it and select Save As. In the dialogue box that pops up, replace dat with xls and hit the Save button.
3. Minimize the mail app and locate the saved file. Right-click on it and rename it to any name convenient, then hit Enter.
4. Right-click on the file and hover on Open With, then select Excel.
3. What app opens the winmail DAT file on Mac?
TextEdit does. Since the Winmail.dat file is often text-based, TextEdit will usually open it. However, if it is an attachment, you should use the online tool; Winmaildat.com.
Dat files are files often created by Windows Exchange. Most Mac users come in contact with it from a Mail send with the Windows Outlook app. If you frequently receive these files, this article has five different ways to open them. I’ll suggest you install an app like TNET’s Enough. Thank you for stopping by; now you’ve seen how to open the .dat file on Mac, share with us in the comment section which method works for you.
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