File extension DAT is just not connected with some kind of program. Technically it may store several types of information and other software programs use DAT files to save data. So to be able to open DAT file you should know specifically what application created it. Here we are listed a few of the potential DAT file sources and how to deal with them.
Winmail.DAT attachment file
Winmail.DAT is often a Transport Neutral Encapsulation Format (TNEF) file generated by Microsoft Outlook. To open DAT file in TNEF format you must have Outlook installed or work with a specialized online service. Learn more in Winmail.DAT file handling article.
Windows Registry DAT file
Windows operating system uses NTUSER.DAT file to save user specific registry entries. Typically, this file is hidden and there’s no have to open it up directly. To watch registry entries connected with a current user you need to simply open RegEdit and go to HKEY_CURRENT_USER. To learn more about NTUSER.DAT read Windows Registry DAT file handling post.
Video CD DAT file
DAT files are used to save video information in MP4 format on Video CD files.
Minecraft DAT files
Minecraft uses DAT files to save player and levels information. Minecraft DAT files use Named Binary Tag (NBT) file format to save data. To learn more about how to open DAT files from Minecraft read a post about Minecraft DAT files.
McAfee DAT files
McAfee antivirus software uses DAT file to save virus definition information. Virus definition files from McAfee contain latest and up-to-date virus signatures that McAfee antivirus can parse and then use it when scanning computers for viruses. For more info about security updates from McAfee via DAT files visit McAfee Security Update page.
Open Unknown DAT File
In case your DAT file is just not matching to your on the categories described above, you can test to find out if you may you know what is at it by searching from the file. To get it done you may either work with a notepad (ensure that the file will not be bigger than 5-10 MB otherwise notepad can get very slow). But preferably use one of HEX editors to open it. To learn more about how to open DAT file in HEX editor read a post about HEX editors.