Good Morning:
Has anyone happened that Odoo marks communication error?
I´m ussing Odoo 13

When sending invitation emails to users I find the following message:

"Something went wrong! 10061 A connection cannot be established as the destination computer expressly denied that connection

None

10061

None "

I was reading and the possible difficulties have to do with blocked TCP port 25 or something, but I do not have enough knowledge of networks to solve it, what I have tried does not work.

Can somebody help me?