When I hear these 2 sentences, they mean very slightly different things, but they are both correct: -- I'm glad to have received an invitation from Joe. = I'm glad that I received an invitation, so now I an go to the party. Joe sent the mail. -- I'm glad to have received an invitation by Joe. = I'm glad that Joe invited me. In this case Joe did the inviting (either verbally or with a letter) and you're glad that the invitation came to you from Joe and not Mary. The invitation can refer to the physical invitation (like letter inviting you to the party, with the address written on it) or the conceptual invitation (just that Joe invited you, regardless of whether it was via mail or email or whatever). A physical invitation is from someone. For the conceptual invitation, you can say you were invited by Joe, meaning Joe did the inviting.

In this sentence, use "from", since "him" is where the invitation originated. However, you could rephrase the sentence, "I'm glad to have been invited by him", because "him" is the one who invited you. When describing the origins of nouns, use "from"; when describing who did something to someone else, use "by". I know, it's complicated. Sorry. Hope that helps anyway

i think it cannoy be replaced.

Yeh it can be replaced.