SQL Server 2016 express install error: attempted to perform an unauthorized operation

Never thought it would be this bad when trying to install SQL Server 2016 Express Edition on Windows 10. I had both SQL Server 2014 and SQL Server 2012 installed and was mainly using SQL Server 2014. Then I thought I should upgrade and tried to install SQL Server 2016. I then got this error:

Attempted to perform an unauthorised operation error.

Tried searching about this and there were suggestions about modifying registry key permissions, so I did try to modify some permission on a few SQL Server related registry keys but that didn't make any difference.

Then I kept searching and found people suggesting it might be a version clash issue so I uninstalled all SQL Server installations including the 2016 version (which wasn't successfully installed) and started fresh.

Now after more than two days I still cannot install a SQL Server.

Below is the part of the detailed log where the timeline matches with the timeline in the error of Windows Event Log; couldn't paste the whole detailed log as it's too long.

EDIT1: After more searching this is the actual exeption being thrown:

Exception type: Microsoft.SqlServer.Configuration.Sco.ScoException
(01) 2016-10-23 10:36:52 Slp:     Message: 
(01) 2016-10-23 10:36:52 Slp:         Attempted to perform an unauthorized operation.
(01) 2016-10-23 10:36:52 Slp:     HResult : 0x84bb0001
(01) 2016-10-23 10:36:52 Slp:         FacilityCode : 1211 (4bb)
(01) 2016-10-23 10:36:52 Slp:         ErrorCode : 1 (0001)
(01) 2016-10-23 10:36:52 Slp:     Data: 
(01) 2016-10-23 10:36:52 Slp:       WatsonData = HKEY_LOCAL_MACHINE@SYSTEM\CurrentControlSet\Services\FltMgr
(01) 2016-10-23 10:36:52 Slp:       DisableRetry = true
(01) 2016-10-23 10:36:52 Slp:       HelpLink.EvtType = 0x48BB60BC@0xBB814387
(01) 2016-10-23 10:36:52 Slp:       EMBResult = Cancel
(01) 2016-10-23 10:36:52 Slp:       SQL.Setup.FailureCategory = ConfigurationFailure
(01) 2016-10-23 10:36:52 Slp:       WatsonConfigActionData = INSTALL@CONFIGNONRC@SQL_ENGINE_CORE_INST
(01) 2016-10-23 10:36:52 Slp:       WatsonExceptionFeatureIdsActionData = System.String[]
(01) 2016-10-23 10:36:52 Slp:     Stack: 
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.Sco.InternalRegistryKey.OpenSubKey(String subkey, RegistryAccess requestedAccess)
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlEngine.Globals.GetSqlRegistryKeyHKLM(ServiceContainer context, String key, String machineName, Boolean createIfNotFound)
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlEngine.FilestreamUtils.SetFltMgrAttachWhenLoadedKey(ServiceContainer context)
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlEngine.RsFxConfiguration.Install()
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlEngine.FilestreamConfiguration.Install()
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlEngine.SqlEngineSetupPrivate.SetupFilestream(EffectiveProperties properties)
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlEngine.SqlEngineSetupPrivate.Install_ConfigNonRC_Prepare(EffectiveProperties properties)
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlEngine.SqlEngineSetupPrivate.Install(ConfigActionTiming timing, Dictionary`2 actionData, PublicConfigurationBase spcb)
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlConfigBase.PrivateConfigurationBase.Execute(ConfigActionScenario scenario, ConfigActionTiming timing, ConfigBaseAction action, Dictionary`2 actionData, PublicConfigurationBase spcbCurrent)
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlConfigBase.SqlFeatureConfigBase.Execute(ConfigActionScenario scenario, ConfigActionTiming timing, ConfigBaseAction action, Dictionary`2 actionData, PublicConfigurationBase spcbCurrent)
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlConfigBase.SlpConfigAction.ExecuteAction(String actionId)
(01) 2016-10-23 10:36:52 Slp:         at Microsoft.SqlServer.Configuration.SqlConfigBase.SlpConfigAction.Execute(String actionId, TextWriter errorStream)
(01) 2016-10-23 10:36:52 Slp:     Inner exception type: System.UnauthorizedAccessException
(01) 2016-10-23 10:36:52 Slp:         Message: 
(01) 2016-10-23 10:36:52 Slp:                 Attempted to perform an unauthorized operation.
(01) 2016-10-23 10:36:52 Slp:         HResult : 0x80070005
(01) 2016-10-23 10:36:52 Slp:         Stack: 
(01) 2016-10-23 10:36:52 Slp:                 at Microsoft.SqlServer.Configuration.Sco.InternalRegistryKey.OpenSubKey(String subkey, RegistryAccess requestedAccess)

I so wanted to find an answer for this but there isn't one anywhere. Not a real one, not a complete explanation.

The only thing I will be able to help with is... It has to be related to a failure to upgrade from a previous version, something lurking in the registry. Though as I say there is no answer for this, which btw I think is a disgrace on MicroSoft's part, there are an awful lot of people out there with the.

In the end to install SQL 2016 sp 1 on Windows 10 (Pro) I had to totally rebuild my PC and install on a clean Windows 8.1 worked beautifully.

I then did my Windows upgrade and SQL 2016 and all known associates run perfectly.

This may be your only answer.