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Garmin Express for Mac Fails to Accept Garmin Connect Username and Password
The Garmin Express™ program will repeatedly prompt for a username and password when syncing with an existing Garmin Connect™ account if Safari is set to block cookies and website data. Changing the Privacy preferences for Safari on your Mac computer will resolve the issue so you do not have to keep entering your Garmin Connect login credentials.
Instructions to Change the Privacy Settings for Safari
First, quit the Garmin Express application:
Select the black triangle icon in the Apple menu bar (top of the screen).
Select Quit.
Select Quit again.
Then, change the Privacy settings in Safari:
Open Safari.
Select the Safari menu in the upper left corner.
Select Preferences.
Select the Privacy icon.
Safari 13
Uncheck Prevent cross-site tracking and Block all cookies (if checked).
Safari 12
Uncheck Prevent trackers from using cookies and website data to track you and Always block cookies (if checked).
Safari 8 thru 11 - Change the setting for Cookies and website data to one of these:
Always allow
Allow from websites I visit
Safari 6/7 - Change the setting for Block cookies and other website data to one of these:
From third parties and advertisers
Never
Close Preferences.
Restart Safari.
Open Garmin Express.
Garmin Express software will accept a valid username and password entered during the next attempt at syncing with an existing Garmin Connect account.