This article lists and defines four Run keys that are in
the Microsoft Windows XP registry.
Run keys cause programs to automatically run each time that
a user logs on. The Windows XP registry includes the following four Run keys:
Each of these keys has a series of values. The
values allow multiple entries to exist without overwriting one another. The
data value for a value is a command line.
There are some special
considerations for the third and fourth keys in the list, the RunOnce keys:
- Beginning with Windows XP, the values in the RunOnce keys are run only if the user has permission to delete entries from the respective key.
- The programs in the RunOnce key are run sequentially. Explorer waits until each one has exited before continuing with normal startup.
- By default, Run keys are ignored when the computer starts
in Safe mode. Under the RunOnce keys, you can prefix a value name with an
asterisk (*) to force the associated program to run even in Safe
- You can prefix a RunOnce value name with an exclamation
point (!) to defer deletion of the value until after the command
- Without the exclamation point prefix, a RunOnce value is
deleted before the command runs. As a result, if a RunOnce operation does not
run properly, the associated program is not asked to run the next time you
start the computer.
If more than one program is registered under any particular
key, the order in which those programs are run is indeterminate. A program run
from any of these keys should not write to the key during its execution. Doing
so will interfere with the execution of other programs registered under the
key. Furthermore, applications should use the RunOnce keys only for transient
conditions (such as to complete application setup); an application must not
continually re-create entries under RunOnce. Doing so will interfere with