Downloaded TurboTax 2017 but it downloaded the exe file rather than the dmg file. So how do I solve this issue?

If you are an advantage member then both installation files should be in your downloads.

If you are on the Advantage Auto renewal program you get both the Windows and Mac Downloads.  Check the Email, scroll down and there is a part that looks like an invoice, it should say
TURBOTAX ADVANTAGE TY2017 CD W/WIN
AND MAC DOWNLOAD

If you need to download your program…..
https://ttlc.intuit.com/questions/1901289-download-your-turbotax-software-purchase

Access your downloads here
https://shop.turbotax.intuit.com/commerce/account/secure/login.jsp?pagecontext=download

If you ordered 2017 directly from Turbo Tax and bought the wrong one then call in,  Contact Customer Service M-F 5am-5pm Pacific (8-8 Eastern) at
https://support.turbotax.intuit.com/contact/

It looks like I didn't look past the first line in the table of downloads.  The first line indicates it is the Mac down load so I chose it.  Thanks for the assistance!