Trust iEnterprise Mail Sync for Gmail
Follow these steps to whitelist the Gmail automatic sync app from iEnterprises.
Login to G Suite admin panel : https://admin.google.com/
Open Security → API controls (Screenshot - 1 )
Click the link “MANAGE THIRD PARTY APP ACCESS” (Screenshot - 2 )
Check if “iEnterprise Mail Sync” app is listed there
If Yes, hover the mouse over it to see the “Change access” link and trust the app. (Screenshot - 3)
If Not listed, click “Add app → OAuth app name” and search for “iEnterprise Mail Sync” and add the app and trust it as mentioned above. (Screenshot - 4 and 5)
Screen shots -
1
2
3
4
5