From the 2002 General Introduction to the Roman Missal (GIRM) approved for the USA, which can be accessed from
romanrite.com/girm.html :
“68. The Creed is to be sung or said by the priest together with the people on Sundays and Solemnities. It may be said also at particular celebrations of a more solemn character.”
The 2002 Roman Missal’s Order of Mass, n. 19, allows either the Nicene or Apostles Creed at any Mass. (Missale Romanum, Libreria Editrice Vaticana, 2002, ISBN: 8820972719, page 513).
The Creed is optional when there are the Scrutinies, (prayers for the elect who are to be baptised a few weeks later.) From the book Rite of Christian Initiation of Adults: “… then, if required, the profession of faith is said. But for pastoral reasons these general intercessions and the profession of faith may be omitted.” (RCIA, n. 143, 157, 164 edition for Australia and England, n. 156, 170, 177 in the editon for the USA.).
The usual time for the Scrutinies is the Third, Fourth and Fifth Sundays of Lent. However, from the RCIA book with the Australian number “133. … When, because of unusual circumstances and pastoral needs, the period of purification and enlightenment takes place outside Lent, the scrutinies are celebrated on Sundays or even on weekdays, with the usual intervals between celebrations. They are not celebrated on solemnities of the liturgical year” (USA RCIA, n. 146).
At the Easter Vigil there is a renewal of baptismal promises, instead of the Creed.
Similarly if there is a baptism at Mass, from the Rite of Baptism for Children “29. … 2 … c. The Creed is not said, since the profession of faith by the entire community before baptism takes its place.” (The Rites Volume One, Liturgical Press, 1990, ISBN: 0-8146-6015-0, page 374).
And if there is a confirmation at Mass, from the Rite of Confirmation “31. … a) the profession of faith is omitted, since it has already been made;” (The Rites Volume One, Liturgical Press, 1990, ISBN: 0-8146-6015-0, page 492).
If there is an ordination of a deacon, priest or bishop in the Mass, from the rite of “Ordination of Deacons, Priests and Bishops”, n. “The profession of faith is not said, nor are the general intecessions.” (The Rites Volume Two, Liturgical Press, 1991, ISBN: 0-8146-6037-1, pages 28, 39, 66).
If there is a consecration to a life of virginity in the Mass: “12. … b) the profession of faith is not said, even if prescribed by the rubrics of the day”. (The Rites Volume Two, Liturgical Press, 1991, ISBN: 0-8146-6037-1, page 161, 177).
If there is a rite of religious profession in the Mass,
for a temporary profession by a man: “22 … b) the profession of faith may be omitted, even if prescribed by the rubrics of the day.” (The Rites Volume Two, Liturgical Press, 1991, ISBN: 0-8146-6037-1, page 213).
the same for a perpetual profession by a man, n. 52(b), page 221.
same if a man renews his vows, n. 83(b), page 233.
same for a women, temporary profession, 25(b), page 252.
same for a women, perpetual profession, 57(b), page 258.
same for a women, renewal of vows, 90(b), page 272.
If there is a blessing of an abbot “15. The profession of faith is not said in this Mass, and the general intercessions are omitted.” (The Rites Volume Two, Liturgical Press, 1991, ISBN: 0-8146-6037-1, page 304.
Same for the blessing of an abbess, n. 10, page 314.
Regarding the 1962 Roman Missal being used, when the 1970 Roman Missal was introduced, there were severe restrictions, for example, the Instruction Constitutione Apostolica of 20 October 1969:
"14. The individual conferences of bishops are to decide on the date when the texts of the new Roman Missal are to become obligatory, except for the cases that are specified in this Instruction nos. 20-21. It is better that such a date be no later than 28 November 1971 …
IV. EXCEPTION
- Elderly priests who celebrate Mass without a congregation and who might encounter serious difficulty in taking up the new Order of Mass and the new texts of the Roman Missal and Lectionary for Mass, may, with the consent of their Ordinary, keep to the rites and texts now in use.
- Special cases of priests who are infirm, ill, or otherwise disabled are to be submitted to this Congregation.
Pope Paul VI approved this Instruction on 18 October 1969 and ordered its publication for the exact observance of all concerned."
More examples are at
romanrite.com/summorum.html