Adobe Digital Editions 3.0 .exe file

Hello, I currently have Adobe Digital Editions version 4.5, but I'm unable to convert the DRM files to transfer to my Kobo. I get the ebook on my kobo but it still says it doesn't have the required authorization. I've talked to a Kobo agent and tried all suggestions besides downloading 3.0.

Where can I find a safe .exe file for 3.0?

Thanks in advance