Unselect HDR

Hello. I try to upload my blend file in to PasteAll, but I got messages. File to big.
OK I use one HDR World- Enviroment Image. If I unselect the HDR the file be smaller, but where I doing that I don’t know. Maybe I need to delete it and reinstall it later on?
Can you help me.
Thanks in advance.

I solved the problem by my self.
Thank you.