I can not send email from my private email to Outlook account

Hello there.

I have webmail for my website like *** Email address is removed for privacy ***

I can send email to many receivers using google mail or yahoo mail and so on.

But when i send mail to someone use Outlook service. i receive

Mail delivery failed: returning message to sender

and the error code is 550 SC-001 (COL0-MC3-F14)

For the detail , it says that permanent error and will list my mail as spam mail.

It is my business mail and i have sent only 3 or 4 email ,what kind of spam can be ?

Question about Outlook Express