Gloss paint too thick and not dried for over a year!

[Kysi]

I painted the inside of a cupboard last year November with gloss paint. As it was my first time painting with gloss, I didn't know that the Wickes Trade White non-drop gloss was actually too thick to begin with and I just slopped it onto the cupboard interior. As it was awkward to reach inside with a brush and the smell was bad, I rushed the job, keen to get it finished and done with.

For over a year, each time I opened the cupboard doors , I'm greeted with a strong paint smell. Although I let it air out for a few minutes each time I access the cupboards, the fumes would accumulate until next time.

Today, I decided to take everything out and investigate. I dug my fingernail into the paint and it left a dint and the paint felt rubbery. I took a utility knife to cut into the paint layer and it dawned that the the inside layer has still not dried and got slightly congealed paint on the blade and on my hands. I guess the off gassing was due to the uncured paint underneath the skin.

I've since put a heater inside the cupboard to try and bake the paint dry although I'm not sure how effective this is given the thickness of the paint. I cannot sand it down as the paint appears soft and will just gunge up the sandpaper. Is there anything I can do to rectify this silly mistake of mine from 13 months ago?

 

[opps]

Open a window and leave the cupboard open. Airflow is more important than heat.

 

[Kysi]

I have left the cupboard opened. I'm not keen on keeping a window opened at this time of the year but I will use a fan. With proper airflow, how much faster will it dry out?