When an installation is unsuccessful, the installer automatically restores (rollbacks) the original state of the computer. Microsoft Project 2000 takes advantage of this feature during installation. This means that you could cancel the Microsoft Project 2000 installation in the middle of overwriting your Microsoft Project 98 files and still be able to run Microsoft Project 98 when Microsoft Project 2000 setup quits successfully. This also means that you can resume installation if Microsoft Project 2000 setup unexpectedly quits before completion.
Window Installer accomplishes rollback by creating a rollback script. A rollback script is a file containing a linear sequence of operations to perform such as file and registry updates, configuration information updates, user interface notifications, and state information for other operations. Each operation recorded in the rollback script is a direct response of an operation in the installation script. See the table below for some examples of what would go into a rollback script.
|
During the Install Process |
Creating the Rollback Script |
|
Write a registry key. |
If the registry key did not previously exist, then describe how to remove the registry key. If the key already existed, then back up the existing registry key so it can be restored. |
|
Install a file. |
If a file did not previously exist in the folder, then describe how to remove the file. If the file already existed, then back up the existing file so it can be restored. |
|
Create a shortcut to the file. |
If the shortcut did not previously exist in the folder, then describe how to remove the shortcut. If the shortcut already existed, then back up the existing shortcut so it can be restored. |
Rollback scripts are in binary file format for the following reasons:
n Efficiency
n Avoids the need for parsing
n To discourage manual editing
The rollback script and files (.RBS & .RBF) are stored in hidden folders called CONFIG.MSI. RBS files are rollback scripts. RBF files are backups of existing files (Microsoft Project 98).
The Config.Msi folders are created when MSIEXEC.EXE starts copying files from the install point.
The rollback script (.RBS) file is always stored in the CONFIG.MSI folder on the drive where the operating system is installed. The .RBF files are stored in the CONFIG.MSI folder located on the drive where the application that is being backed up currently resides. This is done so that there is no crossing of drives when backing up the application files. Files with a RBS file extension are rollback script files and files with a RBF file extension are backups of existing files. All rollback files and the CONFIG.MSI folder are deleted when the installation completes successfully.
|
|
For more information on disabling rollbacks, see the following Knowledge Base article: Q227181 "How to Manage Windows Installer Local Policies". |
Although there are a number of ways that we can troubleshoot installation issues with Microsoft Project 2000, logging can be a particularly effective way to find out what is happening during the installation process.
Уважаемый посетитель!
Чтобы распечатать файл, скачайте его (в формате Word).
Ссылка на скачивание - внизу страницы.
