I should create a contact form for support requests.

Me: I can't connect to the mail server with the settings you've send me.

Employer: It works. I can send and receive mails with Outlook.

Me: Ok, I will check my code.

Employer: It has to work. I even checked the informations I send you about the mail server settings and they are the correct ones.

I've tried every configuration which could be possible and rewrote my code. It wont work, so I tried to use my own mail server and it worked immediately.

Me: I've tried everything but I can't connect to your mail server. After a while I've tried to connect to my own and it works just fine.

Employer: oh...