Open DAT File

Information, tips and instructions

Open DAT File

File extension DAT is not associated with any specific program. Technically it can store many kinds of data and different software applications use DAT files to store data. So in order to open DAT file you need to know specifically what application created it. Below we will list some of the potential DAT file sources and how to deal with them.

Winmail.DAT attachment file

Winmail.DAT is a Transport Neutral Encapsulation Format (TNEF) file generated by Microsoft Outlook. To open DAT file in TNEF format you need to have Outlook installed or use a specialized online service. Read more in Winmail.DAT file handling article.

Windows Registry DAT file

Windows operating system uses NTUSER.DAT file to store user specific registry entries. Typically, this file is hidden and there is no need to open it directly. To view registry entries associated with a current user you just need to open RegEdit and go to HKEY_CURRENT_USER. For more information about NTUSER.DAT read Windows Registry DAT file handling article.

Video CD DAT file

DAT files are used to store video information in MP4 format on Video CD files.

Minecraft DAT files

Minecraft uses DAT files to store player and levels information. Minecraft DAT files use Named Binary Tag (NBT) file format to store data. For more information on how to open DAT files from Minecraft read an article about Minecraft DAT files.

McAfee DAT files

McAfee antivirus application uses DAT file to store virus definition information. Virus definition files from McAfee contain latest and up-to-date virus signatures that McAfee antivirus can parse and use it when scanning computers for viruses. For more information about security updates from McAfee via DAT files visit McAfee Security Update page.

Open Unknown DAT File

If your DAT file is not matching to any of the categories described above, you can try to see if you can guess what is in it by looking inside the file. To do it you can either use a notepad (make sure that the file is not larger than 5-10 MB otherwise notepad may get very slow). But preferably use one of HEX editors to open it. For more information on how to open DAT file in HEX editor read an article about HEX editors.

Open DAT file on Windows OS

  • If you know the application which uses DAT file use it to open it
  • If DAT file is in Named Binary Tag (NBT) format you should use Minecraft to open it
  • If DAT file is McAfee Antivirus file you should use McAfee Antivirus to read data from it
  • If you don't know which application uses DAT file try opening DAT file with hex editor to see what is inside
  • You can use HxD, WinHex, UltraEdit