SolutionTo fix the "Cannot find or load Microsoft Installer" error you should install Internet Explorer 11. Even if you already have installed it, download and run the specified IE installer which will install all required updates for latest Skype version.
As another solution, you can install KB2533623 update, which also fixes this error. But please keep in mind that according to Skype minimal requirements on Windows 7 SP1 it’s required to use Internet Explorer 11.
As a workaround you can install Skype using MSI-installer www.skype.com/go/getskype-msi