Hi,
The syntax differs from version 5.
{if:field=value}Text{/if} => this will only work for default AcyMailing user fields such as name, email, language... so you could use something like {if:email=myemail@example.com}Some text for a test{/if}
If you want to test a custom field, then you have to write it differently:
field should be var.field and the value should be the dtext for the corresponding field.
{if:var.{subscriber:anrede}=Herr}Herr{/if}{if:var.{subscriber:anrede}=Frau}Frau{/if}
