Drilling into UPVC window frames?

[mumnosbest]

We've just bought roller blinds for our kitchen windows. The instructions say screw the fittings to the window frame. Have any of you ever managed to get a screw into a UPVC frame. Can you drill into them. They are brand new windows so really don't want to make a mess.

Yes, I have roller blinds in my conservatory, fitted onto UPVC frames. Were fitted by the blinds company, not us, but they are fine. If us, no doubt would have been a disaster.

We've drilled into our UPVC conservatory frames to but up roller blinds with no ill effects.

Thanks! We'll give it a go then