In most circumstances, you can upgrade to ShadowProtect 5.0 over an existing 4.2.x or earlier installation. You will need a valid and current maintenance agreement to reactivate the license. 

The exceptions to an upgrade include: 

Installing over a ShadowProtect MSP Version: 

If the existing 4.1.5 installation is an MSP installation, you must use the ShadowProtectSetup_MSP_5.0.exe installation file to upgrade to 5.0. 

Installing over ShadowProtect 4.1.5: 

If your existing 4.1.5 installation is a Desktop/Server/SBS/Virtual Edition installation, then to upgrade to 5.0 you must use the ShadowProtectSetup_5.0.exe installation file. You do not need to uninstall ShadowProtect 4.1.5 before installing 5.0. The installer will upgrade your system from 4.1.5 to 5.0 and preserve your job configurations. 

Installing over Pre-4.0.5 ShadowProtect Versions: 

If your system has a version of ShadowProtect older than 4.0.5 already installed, then you will need to de-activate and then fully uninstall it (including the post-uninstall reboot) before you can install and activate ShadowProtect 5.0.

The language of your product serial number/key must match the language you chose in the 5.0 install wizard at the time you install ShadowProtect. Otherwise the ShadowProtect agent will fail to activate. For silent installs, the 5.0 silent install answer file provides a way to specify the language of the install. 

Reactivate after Upgrading to 5.x: 

Upgrading from 4.2.0 or later should preserve your activation. If you upgrade from an activated 4.1.5 or earlier installation of ShadowProtect to 5.0, you will need to re-activate your license. 
To do this, after performing the upgrade, go to the ShadowProtect user interface's Help menu. Click Product Activation. Fill in any remaining fields (your product key will usually be automatically entered). Click OK to re-activate.