What does that mean? What OS are you running?
If you have exhausted the normal approach, then possible corrupt plist
Try deleting the com.apple.dashboard.plist
In Finder drop down menu >Go>Go to Folder>
copy and paste:
Relaunch Dashboard by a restart, or in terminal.app enter:
This will rebuild the dashboard plist you deleted
MacBook Pro, Mac OS X (10.8.2) 2.4GHz IntelCore i5 320 HD 8GB RAM ParallelsDesktop8.0 iPhone5_iOS6.0.2
Currently Being ModeratedJan 13, 2013 12:03 PM (in response to leroydouglas)
leroydouglas, greetings: Just as a point of information, the dashboard function can vary depending upon model as well as the four finger swipe. The OP has failed to identify which one he has.
I assume you meant to type in F3 key.