I just received an e-mail from BetaNews this morning,


Someone just submitted an 4.0 Alpha of Paint.NET. Do you want us to post this release? We would of course not post it over top of v3.36, but we would post it as a seperate release.

Let me know.

Thank you

Well, that was strange — I haven’t publicly released anything! I have some people on the forum doing some private testing on the install/update changes, but nothing too exciting. So I wondered if one of them leaked it (they didn’t), and inquired further.

As it turns out, there’s another download site that’s hosting a file called "Paint.NET.4.00.Alpha.rar," no doubt based on a trusted user submission. This was then simply forwarded to BetaNews.

So I downloaded the file and pawed around, although I did not run the EXE inside of the RAR. Here’s what I found:

  1. The file size was wrong. Like I said in my previous post, the installer is currently 3.7mb. I really doubt that RAR can compress a heavily LZMA-compressed archive down by another 25%. (Or vice versa)
  2. The file name was wrong. "Paint.NET.4.00.Alpha.exe" is a good guess, but you can see even from the screenshot in my previous post that the file name I’m using is actually "Paint.NET.4.0.Install.exe" (I would put an Alpha in there for an Alpha release though, of course).
  3. The file version of the EXE was wrong. The real one would say for the EXE-inside-the-ZIP. This one was
  4. And here’s the kicker, the file wasn’t digitally signed by me. In fact, it wasn’t signed at all!

The first 3 can be faked easily enough, and I’m not worried about divulging that information. The last one cannot be faked*.

My conclusion was that it’s probably a virus, and so I told BetaNews not to publish the file. If it was a leak, that would be annoying but at least it would be reasonably "safe" (plus it would expire soon anyway, limiting the "damage").

So, how do you verify that you have a "genuine" Paint.NET installer? It all comes down to the 4th one: the digital signature. I sign every release of Paint.NET with a certificate that has the dotPDN LLC name on it. It will show up all throughout the process of downloading and installing it, because Windows and Internet Explorer like to remind you about it about 5 times.

Although, as a digression, the best way to make sure you have a "genuine" Paint.NET installer is to simply go to http://www.getpaint.net/ and go from there.

Anyway, when you run the installer EXE in Windows XP, you will get a dialog like this: (assuming you downloaded the ZIP from the website and ran the EXE from there — using something like WinRAR / WinZIP might not result in this)

Note how it highlights the Publisher name, which is dotPDN LLC. If you click on the name, you’ll get a dialog titled "Digital Signature Details". It should say, near the top, "This digital signature is OK." This is the same dialog you’ll see a little later in this post.

In Windows Vista, UAC will help you out here. You’ll get a dialog like this when you try to run the installer:

The dialog states "dotPDN LLC" again, and has the neutral colors as opposed to the big yellow warning version of the UAC dialog.

You can also verify the signature before you launch the program, which is of course a good thing. You want to get the installer EXE unpacked somewhere, then right click and go to Properties:

Next, go to the tab named "Digital Signatures." If there is no such tab, then the file is not signed and you’re done — the file is not from me, or is corrupted/incomplete somehow. You sould see an entry for dotPDN LLC:

Go ahead and click the "Details" button for the final step of verification:

The key here is "This digital signature is OK." At that point you know the file is "genuine", and neither corrupt nor incomplete.

And hey, if someone says, "Hey I found an alpha of Paint.NET version 4.0!" the first thing you should do is go to the Paint.NET website. If it’s not there, then it’s not real!

And yes, I’ve informed the other download site that the "Paint.NET 4.00 Alpha" is probably a virus and that they should remove it.

* Well, I shouldn’t say it can’t be faked. No doubt someone will hack around and prove me wrong eventually. For now though, it’s a fairly safe statement to make.