How to read Tubotax generated Diagnostic file (xxx.dia2025)

[AhuraMazda]

How to read Tubotax generated Diagnostic file (xxx.dia2025). What application on Windows Desktop will open the file?

[VolvoGirl]

Are you sure Turbo Tax created that file?  Never hear of or seen a .dia file.   The only file would be a sanitized file to send to Turbo Tax for them to look at it.   Then you post the token number in the forum so they can retrieve it.   

[mesquitebean]

How and where did you generate that file?  

[rjs]

Does the file name end with .dia2025 or .diag2025 (with a g)? If it's .dia2025 it's not a TurboTax file. If it's .diag2025, with the g, you can open it with the TurboTax Desktop software for 2025. On the screen that says "Continue Your 2025 Tax Return" click "Find a Tax File." In the Open dialog, in the space for the file name, start to type "diagnostic" (without the quotes). The name of the diagnostic file will come up, and you can select it and open it.

The diagnostic file is the "sanitized" version of the tax return that you sent to an agent. It's the same as the tax return that you sent, but with all of the personal information replaced by X's or other arbitrary characters.