how can i fix my upvc window?

sounds like the locking mechanism has broken and only operating the top spigot or the bottom spigot does not clear the keeper. if you have access to the window from the outside have some one lift the sash as you try to open from the inside if this fails the mechanism has broken and you need to have a repair done. if the window opens when you lift it you need to move the keeper usually one philips head screw might be a self drill type. Please do not attempt if you are not sure what you are doing easy to damage.
regards bob

r.machnik
December 2009