<p>Good Day,</p><p>I have exchange 2013 SP1 CU2 and cannot install anything else. I keep on getting&nbsp;</p>

An Attempt was made to load an assembly from a netowkr location which would have the assembly to be sandboxed. in previous versins of the >net Framekwork.

Exchange 2013 doesn't have rollups, it has cumulative updates.  Please post the complete command you're entering and the complete error message.  If you're using a GUI Setup, run it from the com

Hi,

According to the error above, exchange setup file is copied from a network location. So please try to unblock this file.

Similar thread:

https://social.technet.microsoft.com/Forums/exchange/en-US/3c8c34f5-094f-4647-9e14-a2f2db7ca544/exchange-2013-schema-prep-net-assambly-error?forum=exchangesvrdeploy

Best Regards.

[06/10/2015 16:46:40.0397] [0] **********************************************
[06/10/2015 16:47:57.0227] [0] **********************************************
[06/10/2015 16:47:57.0243] [0] Starting Microsoft Exchange Server 2013 Cumulative Update 8 Setup
[06/10/2015 16:47:57.0243] [0] **********************************************
[06/10/2015 16:47:57.0243] [0] Local time zone: (UTC-05:00) Eastern Time (US & Canada).
[06/10/2015 16:47:57.0243] [0] Operating system version: Microsoft Windows NT 6.2.9200.0.
[06/10/2015 16:47:57.0243] [0] Setup version: 15.0.1076.9.
[06/10/2015 16:47:57.0243] [0] Logged on user: INFGRP\administrator.
[06/10/2015 16:47:57.0289] [0] Command Line Parameter Name='mode', Value='Upgrade'.
[06/10/2015 16:47:57.0289] [0] Command Line Parameter Name='iacceptexchangeserverlicenseterms', Value=''.
[06/10/2015 16:47:57.0289] [0] Command Line Parameter Name='sourcedir', Value='C:\Users\administrator.INFGRP\Downloads\Exchange2013-x64-cu8'.
[06/10/2015 16:47:57.0383] [0] RuntimeAssembly was started with the following command: '/Mode:Upgrade /IAcceptExchangeServerLicenseTerms /sourcedir:C:\Users\administrator.INFGRP\Downloads\Exchange2013-x64-cu8'.
[06/10/2015 16:47:57.0399] [0] The registry key, HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Exchange\v8.0, wasn't found.
[06/10/2015 16:47:57.0399] [0] The registry key, HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ExchangeServer\v14, wasn't found.
[06/10/2015 16:47:57.0399] [0] Copying Files...
[06/10/2015 16:47:57.0414] [0] Starting copy from C:\Users\administrator.INFGRP\Downloads\Exchange2013-x64-cu8\Setup\ServerRoles\Common to C:\Windows\Temp\ExchangeSetup.
[06/10/2015 16:48:00.0774] [0] Finished copy from C:\Users\administrator.INFGRP\Downloads\Exchange2013-x64-cu8\Setup\ServerRoles\Common to C:\Windows\Temp\ExchangeSetup.
[06/10/2015 16:48:00.0790] [0] File copy complete. Setup will now collect additional information needed for installation.
[06/10/2015 16:48:00.0790] [0] Assembly dll file location is C:\Windows\Temp\ExchangeSetup\Microsoft.Exchange.Setup.Console.dll
[06/10/2015 16:48:00.0821] [0] [ERROR] An attempt was made to load an assembly from a network location which would have caused the assembly to be sandboxed in previous versions of the .NET Framework. This release of the .NET Framework does not enable CAS policy by default, so this load may be dangerous. If this load is not intended to sandbox the assembly, please enable the loadFromRemoteSources switch. See http://go.microsoft.com/fwlink/?LinkId=155569 for more information.
[06/10/2015 16:48:00.0821] [0] CurrentResult SetupLauncherHelper.loadassembly:444: 1
[06/10/2015 16:48:00.0836] [0] The Exchange Server setup operation didn't complete.  More details can be found in ExchangeSetup.log located in the <SystemDrive>:\ExchangeSetupLogs folder.
[06/10/2015 16:48:00.0836] [0] CurrentResult main.run:235: 1
[06/10/2015 16:48:00.0836] [0] CurrentResult setupbase.maincore:396: 1
[06/10/2015 16:48:00.0836] [0] End of Setup
[06/10/2015 16:48:00.0836] [0] **********************************************

[06/10/2015 16:47:57.0289] [0] Command Line Parameter Name='sourcedir', Value='C:\Users\administrator.INFGRP\Downloads\Exchange2013-x64-cu8'.

Did you download directly to this directory, or was the setup file copied from somewhere else?  If it was copied from a different machine, first unblock the original downloaded file; THEN copy it to the local Exchange server and run setup.exe.

Quick thoughts:

1. Are you running the setup using "Run as Administrator"?

2. If you right-click on the setup.exe, and choose properties, is there an "unblock" button?  If so, do unblock it.

3. Download CU8 again, then try the upgrade again, or download CU8 to a different machine and transfer it over.

A search of the internet for the exact error you're seeing (An attempt was made to load an assembly from a network location which would have caused the assembly to be sandboxed in previous versions of the .NET Framework) is only yielding articles/blogs concerning MSDN and .NET development items. Nothing Exchange related.