This section explains the important notice for the users regarding the updates. Thank you for your patience and support for the LK Tools and I will fix the errors as soon as possible,
If you found this during authorization process,
- click Advanced.
- click Go to Campaign Monitoring Tool for Gmail (unsafe).
This happens because the Add-on is undergoing a verification on OAuth Scope 2.0 and expected completion date is on 15th of May 2019.