Here's the error sequence from the CBS background (SFC and CheckSUR are clear)
Code:
2015-04-17 05:16:16, Info CBS Appl: Package: Microsoft-Windows-IIS-WebServer-Package~31bf3856ad364e35~x86~~6.1.7601.17514, Update: IIS-HttpErrors, Applicable: NeedsParent, Disposition: Staged
2015-04-17 05:16:16, Info CBS Plan: Package: Microsoft-Windows-IIS-WebServer-Package~31bf3856ad364e35~x86~~6.1.7601.17514, Update: IIS-HttpErrors, current: Absent, pending: Default, start: Absent, applicable: Staged, targeted: Staged, limit: Staged, selected: Default
2015-04-17 05:16:16, Error CSI 00000011@2015/4/17:12:16:16.148 (F) d:\win7sp1_gdr\base\wcp\componentstore\csd_core.cpp(616): Error STATUS_SXS_ASSEMBLY_NOT_FOUND originated in function CCSDirect::GetDeploymentClosureStatus expression: (null)
[gle=0x80004005]
2015-04-17 05:16:17, Error CSI 00000012 (F) HRESULT_FROM_WIN32(ERROR_SXS_ASSEMBLY_NOT_FOUND) #695646# from Windows::ServicingAPI::CCSITransactionAnalysis_ICSIInventory::GetDeploymentInformation(flags = 0, class = ICSIINVENTORY_GET_DEPLOYMENT_INFORMATION_CLASS_CLOSURE (1), information = {dwFlags=00000000})
[gle=0x800736b3]
2015-04-17 05:16:17, Info CBS Failed to call GetDeploymentInformation on deployment: x86_microsoft-windows-w..essmodel-deployment_31bf3856ad364e35_6.1.7601.17514_none_c2791dfd801ab969 [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to get component state. [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to get current state of the deployment [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to get Transaction State for package: Microsoft-Windows-IIS-WebServer-Package~31bf3856ad364e35~x86~~6.1.7601.17514, update: IIS-HttpRedirect [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to get current state. [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to populate updates for package: Microsoft-Windows-IIS-WebServer-Package~31bf3856ad364e35~x86~~6.1.7601.17514 [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to add child package to the strategy [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to add child package to the strategy [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to add child package to the strategy [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to add child package to the strategy [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to add child package to the strategy [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to add package: Package_for_KB976932~31bf3856ad364e35~x86~~6.1.1.17514 [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Info CBS Failed to prepare starting packages [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
2015-04-17 05:16:17, Error CBS Failed to process single phase execution. [HRESULT = 0x800736b3 - ERROR_SXS_ASSEMBLY_NOT_FOUND]
I think this means that the installer is corrupt.
However, you say that you are getting the same error attempting to install from the standalone update?