Schengen Visa-Portugal/Ireland

A friend has a valid Schengen Visa issued at Portugal Embassy in Bangkok. Plans changed and she wants to arrive in Dublin.
Will immigration at the airport accept a valid Thailand passport with the above issued valid visa?

Thanks in Advance

Ireland is not part of Schengen-land.
According the the reliable Delta Airlines website, a Thai passport holder needs a visa to enter the Common Travel Area; which paractically means a visa for Irleand and /or the United Kingdom.

The question maybe, will the airline in Thailand let your friend board without a valid visa???.

It's not even a question of where she arrives; your friend will not be able to visit Ireland at all without a visa for Ireland. Her trip to Europe will be limited to the Schengen countries and having obtained a Portuguese visa she will be expected to land in Portugal first.

If she wishes to change her plans, she will need to apply for an Irish visa. If she wishes to visit the UK, including Northern Ireland, she will need to apply for a UK visa.

#1 - I'm afraid that is inaccurate. As #3 says, if a visa-required national wants to visit the Republic of Ireland, they will need an Irish visa. If they want to visit the UK, including Northern Ireland, they will need a UK visa. If they want to visit both, then they will need both visas (unless they fall under the terms of the Irish visa waiver scheme for visitors from certain countries to the UK).

The Common Travel Area is a red herring here - it only applies to Irish and UK nationals, although it does have some implications for nationals of third countries entering the UK via the Republic of Ireland, since there are not usually immigration checks on such arrivals (however, there are systematic immigration checks on arrivals to the Republic of Ireland from the UK, except across the land border).