The IRS e-file window does not open until January 27, 2020. See the attached link to the IRS website with the details on the Filing Season start date.

IRS Filing Season Start Date

Although you can still complete your taxes in TurboTax, the system will not file them until the filing season opens.

Still cannot efile and the window is open.. yet the message that pops up says it is not. I've done all updates. 

Please try refreshing your browser and clearing out your cookies. If that does not work, try clearing out your browser's cache. You may also want to try a different browser. 

Please see below for information on how to delete your cookies. 

https://ttlc.intuit.com/community/troubleshooting/help/how-do-i-delete-cookies/00/25978

Please see below for information on how to delete your cache.

https://ttlc.intuit.com/community/troubleshooting/help/how-to-clear-your-cache/00/26135

If you would like to contact customer support for additional assistance please see below. 

https://ttlc.intuit.com/community/using-turbotax/help/what-is-the-turbotax-phone-number/00/25632