Software Center – Application / Task Sequence stuck on Installing

Run Powershell Elevated

Are you seeing task sequences enter invalid states? 

gwmi -Namespace root\ccm\SoftMgmtAgent -Class CCM_TSExecutionRequest -Filter "State = 'Completed' And CompletionState = 'Failure'"

Clear the entry

$c=(gwmi -Namespace root\ccm\SoftMgmtAgent -Class CCM_TSExecutionRequest -Filter "State = 'Completed' And CompletionState = 'Failure'"); if ($c) {$c.Delete(); Restart-Service ccmexec -force}

or

Start CMD as an Administrator

net stop winmgmt /y

winmgmt /resetrepository

reboot PC

Start CMD as an Administrator

c:\windows\ccm\ccmrepair.exe