slow php mail() delivery- 30 to 60 minutes instead of 1-2 minutes

I have a web-site that has a hosting at some popular hosting company. The problem is that delivery of mail using php mail() function to user emails takes much much more than 1-2 minutes. 40 minutes is the average delivery time I would say... I've contacted the customer support of my hosting company about this issue and they said "No mail server can guarantee a certain time frame for delivery as any mail server can experience a queue if there are multiple requests going through at once. The queuing is usually temporary and should not last long. However please note that if the recipients server is also queuing you may see a wait time over 30 minutes. There is no way to speed this up. "

The hosing is shared (NOT a dedicated server... I don't know if that's important). Any, any ideas on how to reduce the delivery time to 1-2 minutes from 30-60 minutes. (change of our hosting provider is a deal, but not the best one)... Is any other ways 开发者_开发知识库to solve this question? (if yes, please provide step-by-step explanations if it doesn't take too much time)....

Thank you.

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The only way to guarantee faster delivery time is to send mail using a mail server you control, or one which provides such guarantees. You can't just change your code while still using your host's server and get any better guarantees.

http://www.sendgrid.com