WSUS not making available all updates

Solution 1:

Go onto your WSUS server and in the command prompt run WSUSutil.exe /reset. This will Checks that every update metadata row in the database has corresponding update files stored in the file system. If update files are missing or have been corrupted, WSUS downloads the update files again.

Solution 2:

Try the steps given below:

@echo on
net stop wuauserv
del /F /Q %windir%\"Windows Update.log"
cd %windir%
ren SoftwareDistribution SoftwareDistribution.old
regsvr32 /s softpub.dll
regsvr32 /s initpki.dll
regsvr32 /s mssip32.dll
regsvr32 /s msxml3.dll
net start wuauserv
wuauclt /resetauthorization /detectnow
PAUSE
notepad "%windir%\WindowsUpdate.log"
PAUSE