Error 1603 occurs at times on installation and there are many potential causes that need to be eliminated.

Message Received

Windows Installer installed the product. roduct Name: Velixo Reports Pro for Excel and MYOB Advanced 4.0.0.22139. Product Version: 4.0.0.22139. Product Language: 1033. Manufacturer: Velixo. Installation success or error status: 1603

Resolution

Microsoft Link:

https://support.microsoft.com/en-au/help/834484/you-receive-an-error-1603-a-fatal-error-occurred-during-installation