Hi,
I have JomSocial installed. I want to change the Custom Prefix for JomSocial from "jomsocial" to "network". So, I go into the extensions section and enter "network" in the provided box for Custom Prefix on the com_community line. I save(apply) my change, but it still shows mysite.com/jomsocial instead of mysite.com/network when I go to the front page of JomSocial.
What am I doing wrong?

Thanks!

You should deleted the generated URLs and let AceSEF generate them again after making such changes that affects URLs.