Is there any plugin or script to verify that the email address a user enters is a valid email address?
How about a custom function?
FileMaker Custom Function:IsValidEmail ( text )
validate the format or validate that the address is going to work?
For the first i'm going to guess that their are so many possible permutations of valid email addressing that it would be near impossible to write a calc that can trap for ALL of the possible mistakes.
Here are two possible custom function that you can adapt:
FileMaker Custom Function:IsValidEmailFormat( text )
If you want to know if an email address is valid (if it will work or not) you can use this simple web service that will work with InsertFromURL:
Postcode Anywhere API - EmailValidation Interactive Validate (v1.10)
It will return a JSON response that can be easily parsed.
We once made a Email.Verify function for the MBS Plugin:
Monkeybread Software - MBS Filemaker Plugin: Email.Verify
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