.CRDOWNLOAD file with message inside "This program cannot be run in DOS mode."

So I was trying to download a .exe installer on Google Chrome and somehow the file changed to .CRDOWNLOAD . I decided to open it in Notepad to possibly see an error or something like that. When I opened the file in Notepad, I saw something saying "This program cannot be run in DOS mode." I am very confused and have a few questions about the message like "What is a .CRDOWNLOAD file?" and "What is DOS mode?" or "Am I in DOS mode?"I have some details about the PC, from Settings. Here is some other stuff that might help finding it out maybe a bit easier. The first part of the .CRDOWNLOAD file is listed below:MZ   ÿÿ ¸ @ Ø º ´ Í!¸
LÍ!This program cannot be run in DOS mode. $ ­1éPfÒéPfÒéPfÒ*_9ÒëPfÒéPgÒLPfÒ*_;ÒæPfÒ½sVÒãPfÒ.V`ÒèPfÒRichéPfÒ PE L
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 f Š @ 4  € @       Á¢á( @…      …    €a Há(¨/ There are tons of other things in the file, but Notepad says there's over 10 million characters in the file, so I can't put all of it in this question. I was putting the installer onto a hard drive that wasn't my main one (my Acer). I almost forgot about my details of my device! So here they are: Processor Intel(R) Celeron(R) N4500 @ 1.10GHz 1.11 GHz Installed RAM 4.00 GB System type 64-bit operating system, x64-based processor Pen and touch No pen or touch input is available for this display. I have no idea what I should do but my conclusion is that it might have something to do with my external hard drive.