MrsDux wrote:

We removed the skirting which was
stuck on with some sort of adhesive. We now want to put the skirting
back but the adhesive is still stuck to it. What is the best way to
remove it? We were recommended to use a chisel, is this best or is
there a product which would work better?

Put it face down on a clean floor and hit the stuff with an hammer and
chisel. Don't be such a wuss. It is brittle plastic that might take
some of the timber with it in laces but the bulk of the job is done in
moments and any damage hidden.

Search the group for methods of reaffixing the skirt.