Can’t Defrag or scandisk in Win98

I have a P120 running Win98. I installed Win98 from scratch. I can’t run defrag or scandisk. This is the message I get when I try to defrag.
“Your computer doesn’t have enough free memory to defragment this drive. Quit one or more programs and thentry defragmenting this drive again”
scandisk gets a similiar message.
I know this has something to do with conventional memory..?? How do I fix this so I can run these programs??? thanks