This article was previously published under Q150449
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This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.
Windows 95 includes the AutoPlay feature that allows for automaticactivation of a program when a CD-ROM compact disc is inserted into the CD-ROM drive.
While is is possible to programmatically disable this functionality,Microsoft recommends that developers avoid modifying this behavior. Anysuch modifications will globally affect the operating system, potentiallycreating a situation where AutoPlay fails because it is left "turned off."In this event, there is no interface available to the user to restorenormal operation.
In rare cases, however, it may be necessary for an application totemporarily disable this feature. An example of such a program would be aprogram to catalog compact discs that requires the user to insert compactdiscs to be scanned in rapid succession without running any software fromthe compact discs.
For cases such as this, there are two registry entries that control thisbehavior, one for data compact discs and a different one for audio compactdiscs.
Because there is no API or synchronization object to control access tothese registry entries, it is possible that multiple programs or multipleinstances of the same program could interfere with each other. It is theresponsibility of the programmer to take precautions against this.
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
For data compact discs, the registry entry that controls AutoPlay is abitmask in the following location: