Using LR 5 on my mac, trying to get LR to use gmail when I email out a pic. When I set up the account and try to verify I get error messages that the authorization information is correct, but I am sure I have entered in the username, email and password correctly for Gmail.
Your settings will usually be blocked by Google unless you agree to lower your security settings.
Enter your details as shown in image 1 below and click the validate button.
You should see a LR message that the server settings could not be authenticated.
Launch your web browser and go to your Gmail inbox. Look for a message from Google confirming the authorization attempt was blocked.
Click on the link (highlighted in red) on image 2 below.
You will need to Click on the link “Allow less secure apps”
Now go back to LR and click the validate button and your Gmail account should show as validated.
You can now select a thumbnail from the LR Library and mail it by pressing the keys Control + Shift + M (Cmd+Shift+M on Mac)
The alternative is to set up Google two step verification and make the security application specific to Lightroom.