Problems installing EPiServer 4.x with newer versions of EPiServer and .NET present

This is probably old news for many of you, but I decided to put two common problems with installing EPiServer 4.x in the same blog article. The first problem is caused by the .NET framework 3.0 or newer and the second by EPiServer CMS 5 R1 or newer.

Trying to install an EPiServer 4.x (at least 4.62) site on your computer you might run into the following error message, and the installation is halted: “Failed to register ASP.NET client scripts on this side [The system cannot find the file specified]”.

The quick remedy for this, as described in this forum thread is to temporarily move the folder v3.0, v3.5 etc from C:\WINDOWS\Microsoft.NET\Framework\ (or equivalent) to another location during the installation process. The folders can be moved back when the installation is finished.

An other error message you might encounter at a later stage of the installation, when the status of the installer reads “Running assembly installer for /bin/EPiServer.SchedulerSvc.exe”, is: “Cannot install files: The installation failed, and the rollback has been performed. [The name is already in use as either a service name or a service display name]”.

To avoid this, go to add/remove programs and uninstall the EPiServer Shared component before installing the site. The EPiServer Shared component may be reinstalled afterwards from the EPiServer CMS installation package.