file restoration

when by computer is booting up it pauses with a total of (3) lost files one after another in the form of this message:
“cannot find a device file that may be needed to run windows or a windows application.
#1) vnetsup.vxd
press any key to continue
#2 vredir.vxd
press any key to continue
#3 dfs.vxd
press any key to continue.

at this point my computer boots to the a point just before i have to enter the password and gives me this one final message box. ” unable to load the dynamic link library MSNP32.dll . the system cannot find the file specified”.
I am given the option to click OK which i do , I then enter my password, windows loads up . How can I restore these files and clear up these messages?