While I was programming my EV3 robot on my Windows 10, the Lego Mindstorms software immediately closed, and then Bitdefender Antivirus said that it was some sort of Ransomware. It was Bitdefender that closed the application. It looked like this:

enter image description here

Clicking on "attention required" then shows the following:

enter image description here

So then I pressed "Restore Location" and stored the file into some random directory without even knowing what I was doing.

Now I don't have this problem anymore, but I seem to be the only person who has ever had it. And I also wonder why MSIMGSIZ.DAT is needed for the Mindstorms software since Bitdefender seems to say that it came from the Internet Explorer.

Is there something wrong with my PC?
Or is this occurring because of the Mindstorms Software itself?

Btw, this happened to me two times in a row.


It turned out to be some corruption with the Mindstorms software, according to Lego. It didn't remember my brick because I used the Lego site to update firmware to a version that the software didn't recognize. Even now it still tells me to downgrade.

  • 1
    Instead of uploading you pictures somewhere else you can just add them to your post directly - use an icon with "image", while preparing your question.
    – Alex
    Commented Apr 2, 2020 at 13:03
  • 1
    Did you download your Mindstorms software from LEGO or did you use a 3rd party site? In the latter case it is indeed possible that the package got "updated" with a malware.
    – zovits
    Commented Apr 2, 2020 at 13:06
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    The MINDSTORMS software is build on Microsoft Silverlight, which is a web technology, so that could explain the connection to the Internet Explorer folder. Commented Apr 2, 2020 at 15:14
  • First of all, the application was installed from Lego. Second of all, the EV3 Brick's firmware was updated from V1.09E to V1.10E and the Mindstorms software was updated, too. I'm sorry for not giving this information in the first place. Commented Apr 2, 2020 at 15:51
  • I don't think this is something we can help with unfortunately. You might be able to raise this issue with LEGO directly with their support team Commented Apr 6, 2020 at 11:36


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