We recommend that you keep the Multiple Opens box checked unless you have a particular reason not to. This will ensure compatibility with the greatest number of present and future applications that you might want to use.
If Multiple Opens is checked, a particular board can be opened for access from multiple places, either within a single process or by multiple processes. However, the features available through subsequent opens are limited. This mode is needed by certain complex applications that, for example, use separate processes for capture and overlay. Multiple Opens should be checked when utilizing Windows Media Encoder.
If Multiple Opens is unchecked (hunt mode), a particular board can be opened for access from only one place in one process. If there are multiple boards in the system and an application tries to access a board that is already in use, the driver hunts for the next available board. This is the easiest way to start multiple copies of some applications.
Changes you make take effect when you click OK to close the dialog. Applications such as VidCap32 will not pick up changes until you restart them.
Review Appendix F - Multiboard Installations in the User's Guide for more information.