With the public release of Vista a week back, soon developers will be wondering how to write and debug IFilters in the vista environment. Here's a quick and easy way, in addition to the one stated by Marco under Chronicles of an IFilter development - inception to deployment.:
1. Disable back-off (this prevents the indexer to stop when Windows events are generated):
HKLM\Software\Microsoft\Windows Search\Gathering Manager:DisableBackOff = 1
2. Disable filter host termination:
HKLM\Software\Microsoft\Windows Search\Gathering Manager:DebugFilters = 1
3. Restart the WSearch service.
4. Attach a debugger to SearchFilterHost.exe.
5. Set break points in your IFilter dll.
6. Set symbols for your IFilter.
7. Touch the file of interest by opening it and modifying it slightly.
8. Wait for Break Point to hit.
9. Start debugging.
Note that the FilterHost process is the same in vista and WDS.