When you right-click on Windows explorer after selecting multiple files or folders, Windows presents a context menu which is different from the one you get when you select a single file or folder. Often this context menu is reduced with several items such as open, print and edit missing. Recently Microsoft published an article explaining why this happens and how to fix it.
The reduced context menu is not the result of a bug but is a ‘feature’ of Windows. These context menu items are deliberately made to disappear when the user selects more than 15 items to prevent users from accidentally performing these actions on a large number of files.
For those, who wish to have this restriction removed, Microsoft has detailed a very simple registry hack.
Launch Windows registry editor (regedit) and navigate to the following key:
Here you will find a DWORD key called MultipleInvokePromptMinimum, the value of which is set at 15. This key defines the number of files that may be selected while maintaining the context menu options. If the key is not present in your instance of Windows, you can simply create it.
A value of 16 or higher is interpreted as "unlimited" for showing the options from the context menu. However, it does not allow the actual opening of the documents selected if selecting more than 16. To allow the opening of more than 16 documents, set this key to a decimal value greater than the amount of documents you wish to open.
Microsoft recommends only increasing this value to a reasonable number in a controlled environment and only where users really need this value increased.
To see the effects after changing the value of this key, logoff and back on or restart explorer. You can also restart Windows.