Hello Kimberly,
The first time that GTB is run, or if GTB hasn't been run for over 30 days, Google requires that the user authorises GTB to access your tasks. This is a standard security measure implemented by Google to protect your data. Click on the [Authorise] button to be taken to the Google Accounts authorisation screen and click [Allow].
Once authorised, you will be taken to the GTB main menu. Here you can choose what you would like to back up. The option are;
If you are performing a full backup, I would recommend selecting all 3 options. For details on each option, click on the question mark next to each option.
Click [Retrieve Tasks] to start the process of retrieving your tasks from the server. The amount of time taken to retrieve your tasks depends on how many tasks you have, and can vary from a fee seconds to several minutes. The next screen will display progress, updating progress every 6 seconds.
The first time that you run GTB, Google may display another Google page asking you to accept that GTB would like to view your tasks. Click [Accept].
Once all the tasks have been retrieved from the Google Tasks Server, a new screen is displayed where you can choose the file format that would like to use for the export of those tasks.
When backing up your tasks, I would strongly recommend the Import/Export GTBak format. Do not adjust for local timezone. Click the [Export tasks data] button to start the export. How the downloaded file is handled depends on how your browser has been configured.
From the GTI main menu, choose the import method. When restoring a backup (e.g. into a brand new empty Gmail account), I would recommend the Create new tasklist option. For details of what each option does, click on the question mark to the right of each option.
Click on [Choose file] or [Browse] (depending on the browser) and select the file that was exported using GTB.
The first time that you run GTI, Google may display another Google page asking you to accept that GTI would like to manage your tasks. Click [Accept].
The amount of taken for the import depends on the number of tasks and can take from a few minutes to several hours (it takes much longer to create a task than it does to retrieve it). The screen will display progress, updated every 6 seconds.
NOTE1: There is a known server error where the server sometimes returns AccessTokenRefreshError: invalid_grant. If this happens, just restart GTB or GTI and start again.
NOTE2: JavaScript must be enabled in your browser to use GTB or GTI
Regards,
Julie Smith
GTB/GTI Developer