max number of connections per ip

[Esteban L]

I have been haunted by the following error message or months, that we
see using Thunderbird.

Unable to connect to your IMAP server.

You may have exceeded the maximum number of connections to this server.
If so, use the Advanced IMAP Server Settings dialogue to reduce the
number of cached connections.

If I change my location, via a VPN, the error message goes away and I
can connect.

I have edited my /etc/dovcot/conf.d/20-imap.conf file by adding the
following:


protocol imap {
  # Space separated list of plugins to load (default is global
mail_plugins).
  mail_plugins = $mail_plugins imap_quota

  # Maximum number of IMAP connections allowed for a user from each IP
address.
  # NOTE: The username is compared case-sensitively.
  mail_max_userip_connections = 500
}


And, I still get the error message. I know myself, I have about 8-9
accounts, some with as many as 10 folders (I know each one count's as
it's own mailbox), as does my partner--who would access the internet
from my IP.

Does that number really have to be like 10,000, or something? If so, why
does it start out so small in the first place. If not, what else could I
do to avoid this message going forward??