SYMPTOMS
You may experience either of the following symptoms:
1394 devices do not enumerate when plugged into the 1394 bus.
1394 devices can disappear from the 1394 bus when other 1394 devices are plugged into the 1394 bus.

CAUSE
The 1394 OHCI host controller driver contains a problem that sometimes prevents stable enumeration because it cannot acquire a consistent gap count across all nodes.

RESOLUTION
A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Windows XP service pack that contains this fix.