can not send mail to some address

[fzx5v0]

hi

I am having my mail bounced from some addresses and not receiving some mail. here is the error

while talking to mx.somedomain.com.:
>>> DATA
<<< 550 mail09: Host 83.149.123.83, error: R4.1 550 5.1.1 <user@somedomain.com>... User unknown <<< 503 valid RCPT command must precede DATA

I thought it was an authetication problem with smtp but I can send to some external e-mail addresses. I also checked that I was not on any spam database (I do not spam but just in case)

I can not seem to work out what the problem is

Thanks



Easyinkz Printer cartridges

http://www.easyinkz.co.uk

 

[fzx5v0]

found the problem mistake in DNS

Thanks

Easyinkz Printer cartridges

http://www.easyinkz.co.uk