I'm using imgburn to burn disc, i notice even though i only burnt 2gb on the dvd+r, it doesn't allow me to burn new data on the disc and i have to use a new disc.

I can't remember last time i use other software i can continue burn data as long as it has enough space, so what should i disable? I'm not sure imgburn just closes each session or it has finalized the disc so no new data can be added?

If you are using multi-session data burning then the reason is because no more space on the media. Usually with multi-session, even though you have the same files to burn, it will create a new session for the data. Actual fact, multi-session can waste valuable disc space easily as it also needs space to create a file index table for the new session. If you notice all the multi-session discs burned, there are gaps between each session (disc space wasted).

Thus if you want to fully utilize the media capacity, then compile all the files you want to burn together (at least 4.35GB total) and then burn as no multisession (finalize disc after burning).

i don't know i use imgburn with default settings. I burn only 2gb still have more than 2gb on disc but try to burn small files on it it doesn't let me click, then try nero on the burnt disc it eject ask me put new disc. so i assume imgburn already sealed off the disc, how to disable it?