Group policy client side extension group policy shortcuts

hi Everybody

I installed 2008R2 As a Domain controller,I have 300 Windows Xp Client ,I installed Credssp on all Clients,

all clients gets preferences and shortcuts without any problem except of  2 or 3 clients.When I checked Eventvwr.msc \Application I see 2 Error:1085 (Group policy Clients-side-Extension Shortcuts Failed to Execute)

In fact,I Dont like reinstall operating System.

any help would be appreciated.