The data value of the RunOnce key is shorter when you use Windows Installer 2.0 or later (835461)

INTRODUCTION

If you install a Microsoft Windows Installer package by using a version of Windows Installer that was released earlier than version 2.0, the length of the data value of the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce key is 31 characters.

However, if you install a Windows Installer package by using Windows Installer version 2.0 or later, the length of the data value of the RunOnce key is 30 characters.

MORE INFORMATION

By default, the length of the data value of the RunOnce key is 30 characters in Windows Installer 2.0 or later. However, sometimes the length of the data value of the RunOnce key must be 31 characters. In such cases, you must prepend a special character to the data value of the RunOnce key to make the RunOnce key 31 characters long.

REFERENCES

For more information, visit the following Microsoft Developer Network (MSDN) sites:

http://msdn.microsoft.com/library/en-us/setupapi/setup/run_and_runonce_registry_keys.asp

http://msdn.microsoft.com/library/en-us/msi/setup/forcereboot_action.asp

For additional information, click the following article numbers to view the articles in the Microsoft Knowledge Base:

137367 Definition of the RunOnce keys in the registry

827020 HOW TO: Control system restarts in a Setup project that you created by using Visual Studio .NET