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First, as a test, disable the Quick-hide feature:
In Fences 5, this feature can be found under the “Hide” tab of your Fences Configuration application:
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Other versions of Fences may have the quick-hide featuresetting located under the “Vanish” or “Quick-hide” tab:
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If this does not help, please make sure you have not inadvertently put the Fence on an alternate Desktop “desktop page” using Desktop pages. Disable Desktop pages Pages. Ensure Pages is disabled to see if the Fence \ Icon is returned returns to your main desktop:
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Automatic Layout
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https://support.stardock.com/space/SHC/1331396652
The restoring Then restore a recent Fences layout Backup/Snapshot:
https://support.stardock.com/space/SHC/1331331082/How+do+I+use+snapshots+in+Fences