In this chat message I was attempting to say that I was installing Ubuntu on a friends laptop. What I wrote was,
I had a friend for whom I installed Ubuntu on his laptop.
Grammatically, it seems like it works: if I switch around the sentence a bit, I would still use the same kind of prepositional phrase:
I installed Ubuntu on a friend's laptop for him.
Also, if I simply replace the
his for an
a, it sounds right:
I had a friend for whom I installed Ubuntu on a laptop.
However, how I initially wrote it, it doesn't sound right. Is what I wrote initially correct, and if not, why not?