pagefile for windows 2000 server

i have windows 2000 server installed on my server. I keep getting the error that there is no paging file. I go into the page file and change the parameters for the size of the page file and it is accepted. I can also find the pagefile by doing a search, but i keep getting the error that it doesnt exist or that it is to small. any ideas how to stop the error or fix the problem?