There´s a lot of work to do with this formula, but to start with:
IF ( INCLUDES ( Email_Failed_Formats__c , "firstname.lastname" ), "FirstName.LastName; ",null ) &
IF ( INCLUDES ( Email_Failed_Formats__c , "firstinitial.lastname" ), "LEFT(FirstName__c, 1).LastName; ",null ) &
IF ( INCLUDES ( Email_Failed_Formats__c , "firstname.lastinitial" ), "FirstName.LEFT(LastName__c, 1); ",null ) &
IF ( INCLUDES ( Email_Failed_Formats__c , "firstnamelastinitial" ), "FirstNameLEFT(LastName__c, 1); ",null ) &
IF ( INCLUDES ( Email_Failed_Formats__c , "firstinitiallastname" ), "LEFT(FirstName__c, 1)LastName; ",null ) &
IF ( INCLUDES ( Email_Failed_Formats__c , "firstnamelastname" ), "FirstNameLastName; ",null ) &
IF ( INCLUDES ( Email_Failed_Formats__c , "firstname_lastname" ), "FirstName_LastName; ",null ) &
IF ( INCLUDES ( Email_Failed_Formats__c , "lastnamefirstinitial" ), "LastName.LEFT(FirstName__c, 1); ",null ) &
IF ( INCLUDES ( Email_Failed_Formats__c , "lastname.firstinitial" ), "LastName.LEFT(FirstName__c, 1); ",null ) &
IF ( INCLUDES ( Email_Failed_Formats__c , "firstname" ), "FirstName; ",null ) &
IF ( INCLUDES ( Email_Failed_Formats__c , "lastname" ), "LastName; ",null )
It isn´t returning the name of the contact in any of these formats, despite the fields being correct.
I'm hoping to show the name of the contact in a format that depends on what is chosen in the multi-select picklist.
For instance, if "firstname.lastname" is chosen in the multi-select picklist, that should result in "John.Smith" appearing in the formula text field. If "firstinitial.lastname" is chosen, that should result in "J.Smith". And so on...
Part of the problem seems to be the spacing between the"FirstName" and "LastName" fields, but the method suggested below results in a syntax error (Found 'LastName').