Sunny, Gmail and Hotmail(Outlook) blocks messages from uCoz.
I can't agree. I personally use Gmail (a number of different boxes) and I don't have any problems. I don't even remember when was the last time a message from uCoz got into Spam instead of Inbox. Though it happens sometimes. According to my experience, uCoz doesn't usually have any problems with Gmail. As for Hotmail, it's more problematic, but again, not all messages are blocked. I tested a hotmail account just last week, and the message (after registration) was received (though into Spam).
but why they blocking "uCoz" Emails? Some of my Hotmail (or Live) and Yahoo members has registered. But some not receiving the confirmation link... :\
As to "why" - it's not a secret that not all uCoz users follow the rules, and some of them are often sending spam e-mails with uCoz links. That's why e-mail services get suspicious sometimes.
You also prove that not all users using Hotmail etc. have problems. And maybe it's not the e-mail service to blame, but rather user settings (e.g. to delete all message that get into Spam). If a user receives e-mails not through the web interface, but through an e-mail client, then the problem may be in the client settings.
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