Summary

This article discusses how to always overwrite files in InstallShield Express.

Discussion

The Windows Installer engine uses File Versioning Rules to update or overwrite files on the system. However, sometimes setup authors must overwrite or update files regardless of version or date stamp.

NOTE: For more information on file versioning rules, refer to How are Files Overwritten by Windows Installer Service?.

InstallShield 12 Express and Earlier

The recommended method for forcing files to be overwritten is to use the Always Overwrite property. Follow these steps:

1. Navigate to the Files view under Specify Application Data.
2. Find the files that you always want to overwrite existing files.
3. Right-click the file and choose properties from the menu options.
4. Select the Advanced tab.
5. Select the Always Overwrite radio button.
6. Click OK.

InstallShield Express 5.0 and Earlier

The Windows Installer Service also provides the REINSTALLMODE property. This property can be set to various command-line arguments to control how files are installed on the machine. However, by using this property it will force all files in the setup to overwrite existing files. This property should be used carefully. This property can be used in place of the method described above but is not recommended.

To always overwrite files using the REINSTALLMODE property, you must set the REINSTALLMODE property to 'amus', where 'a' refers to always overwriting, 'm' and 'u' refer to rewriting all registry data, and 's' refers to rewriting shortcuts. For more options that can be passed to REINSTALLMODE, see Sending a Minor Upgrade to an Existing Product Without Uninstalling/Reinstalling.

Setting the REINSTALLMODE Property in Your Setup

1. You can pass the property REINSTALLMODE=amus to the installation via the following command-line parameters:
   • MsiExec.exe /I project.msi REINSTALLMODE=amus
   • Setup.exe /V" REINSTALLMODE=amus".
2. To automate the process, you can pass the property REINSTALLMODE=amus in the Setup.ini file. This way when setup.exe is launched, these parameters are passed to the MSI package automatically for you. Follow these steps to specify this parameter in the Setup.ini file:
   1. Open the Disk1 folder under the Release location to locate the setup.ini file. The Release location can be found by selecting Tools > Options in the Express IDE.
   2. On the File Location tab in the Options dialog, note the Project Location field.
   3. Open the setup.ini file from the respective folder using Notepad.
   4. Under the [Startup] section in the setup.ini file, set the CmdLine to:
      CmdLine = REINSTALLMODE=amus
   5. Save the setup.ini file and burn your setup CD or deploy your setup files.

If Using the SingleImage Compressed Option

If building the release with the SingleImage compressed option, you will not see the Setup.ini file in the release location, as it is compressed inside the setup.exe file. To work around this, you can set the Setup.ini file found in the Support directory to incorporate the above command-line arguments. Follow these steps to accomplish this:

1. Go to <DRIVE>\Program Files\InstallShield\Express\Support and locate the Setup.ini file.
2. Under the [Startup] section in the setup.ini file, set the CmdLine to:
   CmdLine = REINSTALLMODE=amus.
3. Save the changes made to the Setup.ini file and rebuild your compressed release to ensure that these changes are included in the setup, as this updated setup.ini file will be included in the setup.exe file.
4. After deploying your release, be sure to revert the Setup.ini file in the <DRIVE>\Program Files\InstallShield\Express\Support location back to its original state, i.e., delete the changes made to the Setup.ini file.

NOTE: <DRIVE> in the paths specified above should be replaced by the drive letter where Express is installed on the machine. e.g., C:\, D:\, etc.

InstallShield X and Later

The InstallShield X Express and later versions contain an enhancement that will allow you to workaround this Windows Installer limitation. To use this product enhancement select the Always Overwrite option contained on the File Properties view.

Additional Information

In Express 3.5 through 5.0, you can set the REINSTALLMODE property via a VBScript custom action. For more information on setting properties via VBScript custom actions, refer to Setting or Getting the Value of a Property Via a VBScript Custom Action.

All the possible values that can be set to the REINSTALLMODE property are as follows:

The above information can be found in REINSTALLMODE Property on the Microsoft Learn website.

The ollowing article discusses the REINSTALLMODE property in some detail:

• Sending a Minor Upgrade to an Existing Product Without Uninstalling/Reinstalling