[Q] I broke my tablet lol topic

I have a cheaper RCA tablet and I recently tried to modify my vold.fstab file and I cannot fond a way to repair the file. I have ADB and all the good stuff. The tablet is stuck on a RCA boot logo at boot. I am familiar with using the command prompt to push files and such. Is there any way I can push my original copy of vold.fstab back in to my system/ect folder? The standard push commands say error:closed. The only way I can get the device to show up in the command prompt is selecting ,update from adb, in the recovery screen. The tablet is rooted but It doesn't boot. Any advice other than replace the tablet? I foolishly did not back anything up before my awesome move of editing a system file I knew nothing about :)