Solved Plugins won't delete (Unable to delete the file)

Trying to help a friend with his server but everytime I try to delete his plugins I get a message saying Unable to delete the file and after a restart the plugins are all back. Any solutions?

 

What happens when try and delete these plugins also the names might help!

 

Using Multicraft by the way.

When I check the boxes and delete the plugins it goes through the normal process of deleting. Then when it gets to the page where it shows the results like (Worldedit.jar removed successfully) it says (worldedit.jar unable to delete the file)

I've also tried connecting to his server through filezilla but it tells me a severe error has occured and doesn't permit access.

List of plugins

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buycraft
colorme
commandbook
dusquisecraft
dynamicban
enjinminecraft
essentials
groupmanager
Giants
Hidstream
spout
slenderman
permissionsbukkit
vault
thor
vanishnopacket
worldedit
eteleport

 

this would be a fault of your host, not of bukkit.
make sure server is stopped, though.

 

Have you tried looking for your server process in task manger this might happen because your just closing the console instead of doing stop then closing it
Try starting the console then if your running from your computer in your task manger right click and hit go to process then end it. post results

 

If bukkit is still running, the file is in use. Therefore, it cannot be deleted. Stop the server first, and try again.

 

Figured it out. According to the host it was an error of some sort and was sorted out.