Q: I have a Msocache folder on my computer. What is it?
A: When you install Microsoft Office 2003 and later versions, the installation media is copied to the local computer into a folder called Msocache. This copy of the installation files is known as a Local Install Source. The Local Install Source lets you avoid having to insert media when you add Office components, repair an installation, or add fixes and service packs. The Msocache is located on an NTFS partition that has at least 1.5GB of free space. If you select the option to Delete installation files during the Office installation, then the Msocache folder is automatically removed. If you want to remove the Msocache folder after Office is installed, run Windows’ Disk Cleanup utility, and after it scans the drive, select Office Setup Files from the Files to Delete list. Click OK. You can only remove the Msocache folder for an Office 2003 installation; in Office 2007, the folder is a required part of the design.