[A] Instructions for enabling IMAP in Gmail account:
 Click on "Gear Box (Settings)" and select "Settings" menu
 Click on "Forwarding and POP/IMAP" tab
 Go to IMAP access and Enable IMAP
[B] Instructions for enabling Gmail account less secure for apps login:
 Click on your Google Account (right top corner - First character of your name) and "Manage your Google Account"
 Click on "Security"
 Check "Allow less secure apps" if Off enabled it by clicking 'Turn On/Off Access'