How to fix Installation is forbidden by system policy error. Hi,1. Which edition of operating system are you using Do you face similar issue with. If you are using windows 7 professional, Ultimate or Enterprise edition then refer the steps mentioned below Try the following and check if the issue persists. Click Start, click Control Panel. Netfx Msi Windows Installer' title='Netfx Msi Windows Installer' />Open Administrative Tools. Open Local Security Settings. Click Software Restriction Policies. Windows 8 Ux Pack 7.0 For Windows 7. Note If no software restrictions are defined, right click the Software Restriction Policies node and select New Software Restriction Policye. Double click Enforcement. Netfx Msi Windows Installer' title='Netfx Msi Windows Installer' />The Most Complete Guide to Visual Studio Toolbox Control Integration. Libor Tinka, Lead Developer, ComponentOwl. Contents. 1. Introduction 2. Prerequisites. Microsoft. NET Framework 1. 1 SP1Service Pack 1 has resolved the issue. However, Microsoft does not provide download to standalone. NET Framework 1. 1 installer that.