How to adjust a upvc window?

My upvc window appears to have dropped. It is opens from the bottom and where the sliding locks are, they wont go over the lip on the window frame. It means that i can only close the window by wedging it up with a screwdriver. Can the window be adjusted in some way?
Chris, February 2008


done
window is not blocked properly when originally glazed,the beads need to be removed and the glass re blocked at the top to lift frame away from glass therefor lifting frame up allowing clearance at bot.

Alex., March 2008
is your window a top opener,you need to ajust hinges from outside,loosen screws on sash push sash up then tighten up screws,if it still happens take sash off then make new holes a couple of millimetes below then try again till working ok.hope this helps

shaun www.sdwupvcrepair.co.uk, February 2008
Its not a tilt and turn unfortunately. Thanks anyway

Chris, February 2008
If the window is a tilt and turn there should be adjustments on the top and side of the window using allen keys. Different manufacturers use different systems but most are variations on this.

faster than a speeding slug, February 2008