Secure the Curling of the Vinyl Floor Tile With an Iron
Vinyl floor tiles curl at the corners as their glue begins to break down, but usually there is still enough adhesion to them that you can’t just pull them out without damaging them. You can use a simple clothes iron to loosen any remaining glue.
As the DIY network shows us, all you have to do is lay down a sheet of aluminum foil to protect the tile surface, then heat it up with an iron over medium heat. The heat will soften the adhesive and make the tile more flexible. Pull the tile upward to apply new adhesive to it, then press down on it. Click the link for full instructions.
How to Fix Curly Vinyl Floor Tiles »Wiki Useful DIY Network via WonderHowTo