We look after multiple Office 365 tenants for hosted Exchange email.  One tenant in particular has an issue where a lot of inbound and outbound emails are marked as phishing.    The domain passes all DNS checks under the Admin console, and I can't find the domain on any blacklist checks.  SPF: v=spf1 include:spf.protection.outlook.com -all  I investigated enabling DKIM, however unfortunately the domain registrar does not accept underscores in CNAME records.  Can someone please help? The issue is very frustrating for our client.  Thanks!
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This is a  about avoiding outgoing mail being classified as spam.   Also related:                    I'm wondering how to prevent my emails from my site being marked as spam? I'm using sendmail.  I'm trying to send emails through my ruby-on-rails application. The mails are all written in swedish (if that does make a difference?). I don't know why they keep getting marked as spam.  Are there any things that I can do to minimize the risk?
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With OpenDNS now needing one to be on the pro package to have filtering turned on, being on a tight budget, we are in need of free DNS filtering.  After reading , I collected SquidGuard blacklists and concatenated domains in the categories i needed into one big list. I then fed it to  generating a file containing about 2 million zones.  named-checkconf parses it just fine, but reloading named takes almost 10 minutes, then it wont resolve anything, and the server slows down to a crawl. Removing the include results in named working properly again.  Whats the proper way to set up BIND9 to work as a DNS firewall efficiently? If it's possible to also block any domain that resolves to specific IP addresses that would solve the whole problem.   I'm running bind as non-authoritative, just a caching server.
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I try to change the URL address from  - I using SharePoint Online (Office 365). Can Microsoft change this address? Or can I create address/record in my private domain, let's says sharepoint.mydomain.com that will be direct to ?   I have make a mistake in  this address and want to change for something different.  Did one way to do something like that is buy a SSL certificate?
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I have servers hosted at a hosting provider and they also host the DNS records for my domain names. Now I want to add subdomains that are resolved by my own DNS service. So for example:   the hosting provider's name server knows the IP address for econemon.com one of my servers knows the IP address for ftp.econemon.com   Also,   unknown or undefined subdomains should be routed to the same IP as the parent domain on failure of my DNS service, it would be great if the requests all go to the IP address that is associated with econemon.com, but I'm not sure how that should work.   Now, I've read through the Wikipedia articles on DNS to dust off my knowledge, but the part that leaves me confused is: how does a client know which server to ask for the IP address for ftp.econemon.com? Does it get that information from the hoster? If so, do I have to register the subdomain there (and what would I need my name server for then)?
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I am implementing a multi-tenant application where my application hosts and serves technical documentation for a tenant's product.   Now, the approach that I was considering was - I host the documentation at docs.&lt;tenant&gt;.mycompany.com and ask my tenant to setup a CNAME DNS record to point docs.tenantcompany.com to docs.&lt;tenant&gt;.mycompany.com.   I want to the site to be SSL-enabled with my tenant's certificate. I wanted to understand if I my tenant company has a wildcard SSL certificate, will it work with this setup or will a new SSL certificate have to be purchased for docs.tenantcompany.com?
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When sending or forwarding emails using a personal or company domain using a  website or email client, how do I prevent the email from being incorrectly marked as spam?
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Can someone explain how Mailchimp does email authentication without user having to update SPF or DKIM records?  Quote from Mailchimp:      When you use MailChimp's authentication, campaigns will pass SenderID, SPF, DomainKeys, and DKIM checks. Since it's turned on by default you don't need to do anything extra in order to enable the authentication of your emails.   But I couldn't find any technical information on how that works.
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I went to stackexchange.com and clicked on SO.  After a few minutes I got a message saying "We have detected too many requests from this IP.  If this is an error contact us."  That was the second SE page I tried to visit.  Second only to SE.com  I moved to another machine and it's working now.  The first machine usually works, I don't know if a got assigned a blacklisted IP or what.  Anyone know what's going on?  EDIT: I would really rather not post my IP on the web, but if a diamond or dev asks I'll email it.  EDIT 2: I looked at badp's dupe suggestion and can verify that I have no scripts frequently calling SO.
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I've just read  which essentially says that when I set up DNS for example.com, the root record can't be a CNAME, it has to be an A record.  My question is, why?   I'm sure the clever people who designed DNS didn't make arbitary restrictions for no reason, but I don't see what we gain by requring root domains to be A records. I would love to just point my example.com domain to someserver.somewebhost.example and forget about it, but I can't.  Please enlighten me, billpg.
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At my current company, all employees have *.com and *.de email addresses. The problem now is that if I search for emails from a certain contact I have to choose between emails from either one of the two. Is there a way to be able to search for both of them at once?
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Is there a way to query our internal DNS entries to discover all the CNAME entries that point to a particular server?  Edit: We're a Windows environment, Server 2003.
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How do I use OpenDKIM with multiple domain names on a single server?  I own 3 domain names, and I have a single server that's running postfix for sending email. How do I use OpenDKIM?  Can I use the same keyfile for all 3 domain names? Do I have to create a TXT record for each domain name?
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Doing a search via regular Gmail frontend in the browser, shows strange results.  I want to search all mails from   *@ebay.*   My search:  from:@ebay   shows also emails sent from an ebay subdomain:   eBay@reply.ebay.com   It seems like Gmail ignores the "@", otherwise I can't see why those messages appear in the search results.  I also tried following searches with no success:  from:"@ebay" from:'@ebay' from:(@ebay) from:("@ebay") from:('@ebay')
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We just made the switch to Google Apps for part of our domain. We disabled the accounts that are now on Google Apps and mail routes correctly. Our problem is that now we have no way of seeing those users in the Global Address List.  So we have these users in our Active Directory, they have no mailbox on Exchange, and we want to be able to see/search for their addresses in the GAL. Is there any way to do this?  This is Exchange 2007, if that matters.
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Q1: Does a DNS rule for *.domain.com match multi-level domain names? In other words, if I just set *.domain.com in my DNS records, will it match all of:  a.domain.com b.a.domain.com c.b.a.domain.com   as many levels deep as needed, with just that one wildcard DNS specifier?  We have a use case for multi-level DNS and I would like to confirm that we are doing the right thing in setting one wildcard DNS setting for the root domain.  Q2: will this work with round-robin DNS?
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When I type mynewdomain.com into my browser I believe the following happens.   My computer sends a request to my ISP's name servers to find the IP address of mynewdomain.com My ISP name server sends a request to the "." name server. The "." sends a response back to the ISP name server, saying try using the com. nameserver. My ISP name server sends a request to the com. nameserver. The com. nameserver finds mynewdomain.com. and sends my ISP nameserver back the A record. My ISP nameserver sends this back to my computer.    My question is about step 5. How does mynewdomain.com. get into the list on the com. nameserver? And given that there are hundreds of millions of registered .coms, how does it find mine in such a short time?
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This is a  about setting up .     I have an office with many computers that share a single external ip (I'm unsure if the address is static or dynamic). Each computer connects to our mail server via IMAP using outlook. Email is sent and received by those computers, and some users send and receive email on their mobile phones as well.  I am using  to generate an SPF record and I'm unsure about some of the fields in the wizard, specifically:   Enter any other domains who may send or relay mail for this domain Enter any IP addresses in CIDR format for netblocks that originate or relay mail for this domain Enter any other hosts which can send or relay mail for this domain How stringent should SPF-aware MTA's treat this?   the first few questions i'm fairly certain about... hope i have given enough info.