"kindly" is rarely used as an adjective, and only when describing people.
Looking for ESL work?: Try our EFL / TOEFL / ESL Jobs Section!
'Kind' is an adjective so modifies the noun 'regards'.
Kindly is an adverb and cannot modify a noun.
You are perfectly correct--kindly can be used as adjective and adverb:
A kindly gentleman, asked me to kindly help him up the stairs.
Myself, i would send kind regards, but kindly regards would no doubt be just as pleasant to the recipient.
Sometimes language is all about what you grew up with. Getting your meaning into another person's ear is the important part, not adhering to the rules of grammar.
People are waiting to help.
Related forum topics: