How to resolve 550 Invalid Recipient error?

[Maddox G]

I am Dell Studio 15(1555)(Intel Core 2 Duo T6600, 320GB SATA Hard Drive, Intel Graphics Media Accelerator 4500MHD, 6GB Shared Dual Channel DDR2 ). I use internet on daily basis for surfing, mailing, downloading movies and songs etc. I only use this laptop and no one else does. Also use McAfee trial version anti-virus. Recently i am having problem in sending mail and came across an error: 550 invalid recipient. Please help to resolve this problem

[Jackson2]

According to my knowledge about computers, this error( 550 Invalid Recipient) would be coming because you are typing invalid user name or user e-mail id which not existing. In other words can say that, this can be happen because the address entering in recipient is unavailable, does not exist or is cannot accept mail temporarily at this moment. There maybe some other reason also behind this.

[johnson22]

There are many reasons behind this error i.e 550 Invalid Recipient. But i can tell you some common reasons for this :
1] The anti virus that is on your machine is running and it is scanning all your outgoing emails and attachments. So try disable the scanning of outing mails.
Just enable the settings for only incoming
2] There may be some software firewalls on your machine that can block port 25. If there is software like this then check their settings and make it correct.
3] May be provider can be blocking or intentionally slowing down your connection to "combat spam". This is because you would be sending large data. So
send the in small-small pieces.

[Trio]

This error( 550 invalid recipient) is like the e-mail address you are sending to is invalid or your not entering the hole address (i.e name@somedomain.com). And also would like ask that this error is coming when the message being sent or after sending message, it comes in inbox? or is it right when you click on the send button?. Try reset your proxy configuration. And if you are on a network and do not have a live connection right to your ISP but I doubt it, then make sure of the address, try sending to other people and see if that works. Hope this you fix your problem.

[deveritt]

I also went through same error few days ago, and now i fix it. So my experience say that error (550 Invalid Recipient) comes due to failure from the receiving server. So you should ask them to receiver or mail server persons, why they are rejecting or not allowing to email and what you do in order to successfully sent the e-mail. Also you do something to test, like try to do settings of Domain Keys to Sign All and check if it helps. May be everything goes fine after this all things is done.

[Techguru01]

I am also same error i.e 550 Invalid Recipient. In my case when trying to send an e-mail to an valid e-mail address with one of my application, i get the error that 550 Invalid Recipient, although the e-mail address which i am entering is valid. I think there should not be any problem about my codes, but it may be due to free SMTP server that I am using. So, please tell me if have to do any configuration with SMTP to allow it relaying?