i bought a glass baking dish,, from marinex similar to this one but in a rectangle shape ..

http://www.warehousedeals.com/Marinex-4.2Quart-Oval-Baking-Dish-GiftBoxed/M/B0016LO436.htm?traffic_src=froogle&utm_medium=organic&utm_source=froogle

someone told me i would be able to use it to bake some salmon.

and now im reading the instructions and it says dont use in a preheated oven.

but i thought you had to preheat the oven every time you want to bake ?

what am i supposed to do .. i have to bake salmon in the preheated oven at 450 degrees F
i dont want it to explode or anything .
someone told me that i could use it but im not sure .

what can i do to avoid it from exploding

**mind that on the baking dish it said that it was oven safe. and then i open it and read the packet and it says dont put it in a preheated oven

so what do i do