MSOSYNC.EXE & symerr.exe - Help Needed

Guys

My PC has suddenly developed a problem which is mystifying me. When the PC starts up I get the following messages:

MSOSYNC.EXE - The procedure entry point is could not be located in the dynamic link library ntdll.dll

ApplySyncNotifier.exe (same)

symerr.exe (same)


Whilst the PC is working it has affected my Norton Security which won't start up along with Start Up Utilities 2012. I also have no restore points and it won't let me make a restore point. Not being up to date with Norton is the most worrying although as I say the computer does work in everything else. I did notice that my CPU went close to 100% usage the other night if this helps.

Any ideas - been driving me nuts this one. I also wasn't sure about posting this here but hopefully I've got the right section.

By way of an update - now itunes won't open - same message.

Folks by way of another update - I happened to stumble upon another thread in this forum which suggest I do a scan through command prompt - well low and behold it has worked. Everything is back working much to my relief.