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Portable applications for Microsoft Windows
Most programs for Microsoft Windows are not designed to be portable. The Windows registry, given the way they are managed bookstores dll, and the structure of Windows Installer, tend to make the installation of the programs is one-way. Many popular applications such as Adobe Photoshop or Microsoft Word, for example, use the record-intensive and information stored in many directories of file system, although it is advisable to use the registry to store only the basic configuration of the application, and the user’s personal directory to store files larger.
To create portable applications, developers must ensure that the leave application where the computer has been implemented completely “clean”. This means that the application should not use the register, or store files anywhere other than its installation directory.

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