What is the ruling on an email message that invites writing "Istighfar" (seeking forgiveness), "Dhikr" (remembrance of God), or "Du'a" (supplication) with the name written next to it, with the aim of gaining reward from others reading it?

There is no harm in disseminating messages that remind people of good deeds such as Tasbih (glorifying Allah), Tahlil (declaring there is no god but Allah), Takbir (exalting Allah), Du'a (supplication), and Istighfar (seeking forgiveness), whether verbally or through messages, for "the one who guides to good is like the one who does it." It is cautioned against associating this with a specific number not mentioned in the Sunnah, or spreading innovated forms of remembrance (dhikr), or attaching a sin to not sending the message. The reward for disseminating messages depends on the sincerity of the doer.