The time period in which computers will check for updates on WSUS server is 22 hours (default). However, you can have the client computer check manually by using the following command line:
wuauclt /resetauthorization /detectnow
If that doesn’t initially work, you can try a little more advanced option here involving removing some registry entries and running the same command to force it to check for updates.
@echo off net stop wuauserv REG DELETE "HKLMSoftwareMicrosoftWindowsCurrentVersionWindowsUpdate" /v PingID /f REG DELETE "HKLMSoftwareMicrosoftWindowsCurrentVersionWindowsUpdate" /v AccountDomainSid /f REG DELETE "HKLMSoftwareMicrosoftWindowsCurrentVersionWindowsUpdate" /v SusClientId /f net start wuauserv wuauclt /resetauthorization /detectnow wuauclt /reportnow
