The following are the possible reasons:

  1. Change of password in the source mailbox account. 
  2. Enablement of TFA/Multifactor Authentication in source mailbox account. Generate an application specific password and use the same in Freshsales IMAP configuration (password field) by editing it. The generation of an application specific password can be obtained by contacting your respective email Provider.
  3. For queries related to certificate change or expiry write to us at