Password reset email never arrives

Dear all -

I have a strange situation on my 2.2.1 vanilla flavor system. I get numerous complaints from users that they cannot reset their password: the reset email never arrives.

I have been unable to replicate the error: all my attempts to reset my password have ended successfully - I get two email messages, one to confirm and the other one with the new password.

No LDAP, no unusual settings. Authentication set to Manual.

I have two questions:

1. Have you ever encountered something to that tune?

2. Where and how can I see a log of password reset requests?

TIA -

Lev