Cannot Open As It Is Not a Valid Paint.Net File

[TecoMS SM]

So I was about to send in my new server logo and I wanted to check it to see if it was the .pdn file or the .png file type. And it was a pdn. file and when I try to open it, BOOM it says Cannot open file as its not a valid paint.net file, and I was saying WHAAAT and I never did like OPEN WITH NOTEPAD or something like that, just opened paint.net and gives me that. Here's the error box (extra info)
 

Application version: paint.net 4.2.10

System.FormatException: file is not a valid paint.net document
   at PaintDotNet.Document.FromStream(Stream stream) in D:\src\pdn\src\Data\Document.cs:line 1344
   at PaintDotNet.FileType.Load(Stream input) in D:\src\pdn\src\Data\FileType.cs:line 522
   at PaintDotNet.Functional.Func.Eval[T1,TRet](Func`2 f, T1 arg1) in D:\src\pdn\src\Base\Functional\Func.cs:line 158

And also yes, I did restart, yes I am on the latest updates of windows (if your not then why?) and I can't find the repair tool as it did not show up and I don't know what was the directory. It took me around 6 hours to make it and it's already corrupted.

(I'm not good at writing these so sorry for the CRINGE if you are a gamer or something)

[toe_head2001]

Can you share the file so we can take a look?

 

 

16 minutes ago, TecoMS SM said:

... so sorry for the CRINGE if you are a gamer or something

 

What's that supposed to mean?

[Ego Eram Reputo]

Sounds like the extension is incorrectly saying it is a PDN. Use this tool to determine exactly what type of file it is: WhatsIt

 

If you find the extension is wrong rename the file (right click > rename)