This occurred all of a sudden. How can I fix this? I can work around it, but would like to know why this happened and if it can be fixed.
It's anyone's guess why it happened, seeing as you didn't provide any details as to ID version, OS, etc.
If there's a fix, it's likely you'll eventually hit it via the usual sequence; replace preferences, reboot, re-install...
Sounds like it might be Windows and large fonts... See InDesign tools and panels don't respond to mouse clicks (Windows 7/Vista)
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