Click on the Start up 
node under your BaseMaps Map Source entry.
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Enter the Max Zoom and Min Zoom to set the maximum and minimum overall zoom for the map.
| Info |
|---|
From v5.8.0 the Min and Max Zoom functionality has been replaced by the Scales to set the zoom limits of the maps. |
| Note |
|---|
From V5.6.2 the Units e.g. METERS have been removed from the MapSource Start Up as they have replaced with a general Map Units setting located alongside the Projection selector in the main MapSource tab. |
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