You can learn more about tracking contact Birthdays in Redtail and Birthday Reminders here. In this post I just want to cover how you would go about enabling or disabling Birthday Reminders for multiple contacts in bulk.
From your Advanced Search page, after running a search that will include your desired contacts, place checks to the left of the names of those contacts for whom you want to adjust their Birthday Reminder settings:
In the example above, I've run a search that yielded 99 records (only partial results are displayed in the screenshot) — I then selected six of those records for whom I want to adjust this setting.
My next step would be to click Options in the Result Options widget to the right of my search results and then to select either Disable Birthday Reminders or Enable Birthday Reminders from that menu:
After clicking one of these options, you'll see a dialog that just asks you to confirm whether or not you want to perform your selected action. After confirming, this change will be reflected within your database.
As you can probably see, it's a quick and easy method to change the Birthday Reminder settings for multiple clients at one time. Note: Birthday Reminders is a searchable field within Redtail CRM, so you can easily search for all records with enabled or disabled Birthday Reminders.