Outlook 2010/2013.
Open Microsoft Outlook 2010 / 2013.
In the home tab, click the Junk drop-down menu.
Then click Junk Email Options.
Navigate to the Safe Recipients tab.
Click the Add button.
Type in the domain (testlio.com), then click okay.
Outlook 2016
Open the Exchange Admin Center.
Click on Protection.
Click on Spam Filter.
Double click on Default.
Click on Allow Lists.
Under Allow Lists, click the + to add a domain (testlio.com).
Office 365
Open the Exchange Admin Center.
Click on Protection.
Click on Spam Filter.
Double click on Default.
Click on Allow Lists.
Under Allow Lists, click the + to add a domain (testlio.com).
Yahoo! Mail
Login to Yahoo! Mail and select settings by clicking on the ‘Settings’ icon
Scroll down the menu and select ‘More settings’
In the left-hand menu select 'Filters'
Select 'Add new filters'
Type a name for your filter - "Whitelist Website Testlio Alerts"
Under 'Set rules', select 'From' as the rule and 'contains' as the criterion for the filter. The filter will be applied to any email that comes from an email address that contains the text you add
Input the domain that you want to whitelist (testlio.com)
Under 'Choose a folder to move to' select 'Inbox'. This ensures that all emails will arrive in the inbox and never be sent to spam
Click save
Once the filter has been successfully created, you can view it under 'Your Filters'
Gmail
Go to Settings
Select Filters and blocked addresses.
Select Create a new filter
In the From field, add @testlio.com
Click Create filter.
Tick "Never send it to spam"
Click "Create Filter".