There may be many causes for the failure of some file of Windows OS, but most of the causes are as follows:
NSPrgMgr.ocx: Download nsprgmgr.ocx File
NSSCORE.dll: Download nsscore.dll File
NSUM.exe: Download nsum.exe File
NSUMPS.dll: Download nsumps.dll File
NSUNIMGR.ocx: Download nsunimgr.ocx File
ne2000.sys: Download ne2000.sys File
netflx.sys: Download netflx.sys File
npdrmv2.dll: Download npdrmv2.dll File
notiflag.exe: Download notiflag.exe File
napipsec.dll: Download napipsec.dll File
napmontr.dll: Download napmontr.dll File
napstat.exe: Download napstat.exe File
ncobjapi.dll: Download ncobjapi.dll File
ncprov.dll: Download ncprov.dll File
ncxpnt.dll: Download ncxpnt.dll File
netsetup.cpl: Download netsetup.cpl File
netsetup.exe: Download netsetup.exe File
nusrmgr.cpl: Download nusrmgr.cpl File
nic1394.sys: Download nic1394.sys File
nikedrv.sys: Download nikedrv.sys File
netfxocm.dll: Download netfxocm.dll File
nshipsec.dll: Download nshipsec.dll File
ntvdm64.dll: Download ntvdm64.dll File
netset03.exe: Download netset03.exe File
NAPCRYPT.DLL: Download napcrypt.dll File
NAPHLPR.DLL: Download naphlpr.dll File
NAPINIT.DLL: Download napinit.dll File
napinit.Resources.dll: Download napinit.resources.dll File
NAPSNAP.DLL: Download napsnap.dll File
napsnap.resources.dll: Download napsnap.resources.dll File