PISKEI TESHUVOS 695 #58 (p.586) cites RAMBAM HILCHOS BERACHOS 11:2 who writes, "For every positive commandment between man and Hash-m ("Bein Adam Le'Makom") whether this is an obligatory or an optional Mitzvah, one makes a Berachah on the Mitzvah before performing it". This implies that for "Mitzvos Bein Adam Le'Chaveiro" - between a person and his fellow man, one does not make a Berachah.

It is true, as you wrote, that REMA OC 695:4 states that if someone sent his friend Mishlo'ach Manos and the latter did not want to receive them, or he said he foregoes ("Mochel") the present, the donor nevertheless thereby fulfilled the Mitzvah. However PRI CHADASH and CHASAM SOFER (cited by MISHNEH BERURAH #24) disagree with Rema.

TESHUVAS HA'RASHBA 1:18 writes that one does not make a Berachah when giving charity to the poor because the recipient may not wish to receive it (you mentioned this Sevara). However Rashba does not mention Mishlo'ach Manos explicitly and one could argue that Rashba agrees with Rema and therefore one would make a Berachah on Mishlo'ach Manos.

I would like, though, to suggest the following idea. There is an alternative possibility. Rema may side with Rambam and even though the donor is "Yotzei" despite the refusal of the recipient, nevertheless he still does not make a Berachah, because on all Mitzvos "Bein Adam Le'Chaveiro" one does not make a Berachah according to Rambam, whether or not the giver is Yotzei. In addition Pri Chadash and Chasam Sofer may side with Rashba - therefore since the donor is not Yotzei if the recipient does not desire it, it follows that one makes no Berachah.

According to the above reasoning, if one thinks it through carefully, it follows that according to absolutely everyone - Rambam, Rashba, Rema, Pri Chadash and Chasam Sofer - one makes no Berachah on Mishlo'ach Manos. Even though we do not know for sure that the Poskim align themselves as stated above, nevertheless "Safek Berachos Le'Hakel" - if one is in doubt one does not not make a Berachah.

KOL TUV

D. Bloom

PISKEI TESHUVOS 695 #58 (p.586) cites RAMBAM HILCHOS BERACHOS 11:2 who writes, "For every positive commandment between man and Hash-m ("Bein Adam Le'Makom") whether this is an obligatory or an optional Mitzvah, one makes a Berachah on the Mitzvah before performing it". This implies that for "Mitzvos Bein Adam Le'Chaveiro" - between a person and his fellow man, one does not make a Berachah.

It is true, as you wrote, that REMA OC 695:4 states that if someone sent his friend Mishlo'ach Manos and the latter did not want to receive them, or he said he foregoes ("Mochel") the present, the donor nevertheless thereby fulfilled the Mitzvah. However PRI CHADASH and CHASAM SOFER (cited by MISHNEH BERURAH #24) disagree with Rema.

TESHUVAS HA'RASHBA 1:18 writes that one does not make a Berachah when giving charity to the poor because the recipient may not wish to receive it (you mentioned this Sevara). However Rashba does not mention Mishlo'ach Manos explicitly and one could argue that Rashba agrees with Rema and therefore one would make a Berachah on Mishlo'ach Manos.

I would like, though, to suggest the following idea. There is an alternative possibility. Rema may side with Rambam and even though the donor is "Yotzei" despite the refusal of the recipient, nevertheless he still does not make a Berachah, because on all Mitzvos "Bein Adam Le'Chaveiro" one does not make a Berachah according to Rambam, whether or not the giver is Yotzei. In addition Pri Chadash and Chasam Sofer may side with Rashba - therefore since the donor is not Yotzei if the recipient does not desire it, it follows that one makes no Berachah.

According to the above reasoning, if one thinks it through carefully, it follows that according to absolutely everyone - Rambam, Rashba, Rema, Pri Chadash and Chasam Sofer - one makes no Berachah on Mishlo'ach Manos. Even though we do not know for sure that the Poskim align themselves as stated above, nevertheless "Safek Berachos Le'Hakel" - if one is in doubt one does not not make a Berachah.

KOL TUV

D. Bloom

Follow-up reply:

Here is an another reason why no Berachah is made on Mishlo'ach Manos. It is based on the MAGEN AVRAHAM 692:1 who writes that when making the "she'Hechiyanu" on reading the Megilah on Purim morning one should have the intention that this Berachah should cover the Mitzvos of Mishlo'ach Manos and the Purim meal as well.

Magen Avraham adds that someone who has no Megilah available at all should not make the she'Hechiyanu blessing on Mishlo'ach Manos and the meal alone, because eating is something one does every day and there is a meal every Shabbos and Yom Tov, so Chazal did not institute a Berachah at all on a Seudah. Magen Avraham implies that not only did Chazal not institute a she'Hechiyanu Berachah on the meal, but in fact they did not fix any Berachah at all for the eating.

There are proofs that the Mitzvah of Mishlo'ach Manos is to a certain extent a part of the Mitzvah of the Seudas Purim. The Gemara in Megilah 7b states that there were Amora'im who exchanged their meals with each other and thereby fulfilled the Mitzvah of Mishlo'ach Manos. See also SHULCHAN ARUCH OC 695 where there is no special chapter dealing with Mishlo'ach Manos but it is included in the chapter dealing with the Purim meal.

According to the above one can conclude that since Chazal did not institute a Berachah on the Purim meal, because a meal is a common occurrence, it follows that they also did not institute a Berachah on Mishlo'ach Manos, because the latter Mitzvah is a branch of the Seudas Mitzvah.

(I received part of the above idea from MO'ADIM U'ZMANIM 2:186 p. 179 by RAV MOSHE STERNBUCH Shlita. Incidentally, I found that I was Mekaven, BS'D, with my first answer, to what Rav TZVI PESACH FRANK ZT'L wrote in MIKRA'EI KODESH PURIM #40 - that Rema agrees with Rambam. See also MAHRATZ CHAYES Megilah 7a who as far as I am aware was the first of many commentaries to raise your question.)

KOL TUV

D. Bloom