1) the file template.msi does not exist in the same folder as the AdvancedInstaller executable or
2) it can not be copied near the project file (the aip with your project).
This can be caused by the fact that in the target folder (where the .aip file is located) there is a file with the same name you want to generate that can not be overwritten (it is opened by another program or you dont have the wright to write in that folder).
I suggest you uninstall and install the application again, or close any other applications that may have these files opened.