vTiger mail manager imap failed

Question

Previously mail manager on vTiger was working and receiving emails. One day ago it suddenly threw an error:

Retrying PLAIN authentication after [AUTHENTICATIONFAILED] Invalid credentials (Failure), 
Retrying PLAIN authentication after [AUTHENTICATIONFAILED] Invalid credentials (Failure), 
Can not authenticate to IMAP server: [AUTHENTICATIONFAILED] Invalid credentials (Failure)

Password and username are correct, checked them by logging into gmail.

Username: [email protected]

I also tried clearing the captcha, didn't help https://www.google.com/accounts/DisplayUnlockCaptcha

I tried installing a totally fresh copy of vtiger crm via softaculous app installer and it still threw the same error.

I then tried installing vtiger on a different server, and STILL it threw the same error.

I finally tried a new gmail address. Again it threw the same error.

But when i tried setting it in vtiger CRM on Demand, it worked.

Answer 1

In my situation the problem came down to the special characters in the password. After removing the special characters from the password it worked! (It even worked with _ but not with + so there may be a few options).