しかしながら

しかしながら means "however", "nevertheless". It opens a sentence that runs against the one before, and it is a formal word for writing, speeches and official statements – a heavier しかし.

It often grants the point before it and then sets a firm objection against it.

しかしながら, しかし or でも

All three mean "but" at the head of a sentence. でも is the word for conversation. しかし is written or careful speech. しかしながら is the most formal, and in conversation it sounds like someone reading out a statement.

• × (to a friend) 行きたいよ。しかしながら、時間がない → 行きたいよ。でも、時間がない

しかしながら is one word. The ながら in it is not the "while doing" ながら after a ます-stem.