Had a terrible time with this error. I use the desktop version of TT, not the online version, so I can't be sure if this would work for online TT users.
Thanks to some dedicated work by James from Turbo Tax and myself, it was determined that the cause of my problem was the McAfee firewall settings. The Intuit Update and Intuit Update Service programs were both set to use dedicated ports (default setting I think). This caused the update process to go into the Not Responding state. Neither McAfee nor TT gave an indication as to what the problem was. The solution was to change the firewall settings within McAfee. Open McAfee livesafe. Click on the 4 boxes beneath the Home symbol, then click Firewall. Expand the Internet Connections for Programs section. Find Intuit Update and click on it. Scroll down to the bottom of the page and click Edit, then change the setting for the program to All Devices and save. Repeat the process for Intuit Update Service. Once those changes are complete, close out of everything and restart the computer. The update should work then. Best of luck.
