SPF records work by identifying the servers that are authorized to send email from your domain. To add subdomains, you must manage your own DNS settings at your registrar's website.
If you are letting Microsoft manage your DNS settings with NS records, you can't add subdomains.
It's important that you have or create only one TXT record for SPF.
If you already have an SPF record, you should append the new Office 365 values to it, rather than create a new one.
This way it ensures that the server can handle emails for the address.
Many SMTP servers actually give back false positive answers as a protection against spammers: to overcome this issue, Email Verify for . NET's unique multithreaded engine lets you perform thousands of validations at once. NET follows Microsoft's event-based pattern and allows for optimal integration with any desktop-based solution.
If you manage your own DNS records and your DNS host does not support all the DNS records that Office 365 needs, some Office 365 features won’t work.
NET's whole architecture let you perform a full email validation with just a single method call, whether the job is as simple as a syntax check or as complex as a mailbox existence test. On top of that, the component exposes various events that notify the user about any change in the e-mail address validation's progress, including verifications starts/ends and depths advancements.
Here is, for example, what it takes to validate an email address using the default settings for the component: With a very stable and mature code base, Email Verify for . This way, whether your project is a desktop-based application, Web-based, or a class library, you may use these notifications to react accordingly at every phase of the verification activity, as well as to present a message to the end user or to insert a row into a database. NET internally employs a very fast, multi-threaded e-mail address validation engine capable of processing hundreds of items at once using asynchronous-based processing logic and different optimization algorithms.
After you've added or updated your SPF record for Office 365 email, you should check to make sure that the syntax is correct with one of these tools: A domain is a unique name that appears after the @sign in email addresses, and after It typically takes the form of your organization's name and a standard Internet suffix, such as or
Using a custom domain like "[email protected]" with Office 365 can help build credibility and recognition for your brand.