Missing Colour Presets I Lightroom 6
I recently upgraded my Lightroom 4 perpetual license to Lightroom 6 via download. The initial download resulted in Version 6.0 only. Nevertheless everything seemed intact including all the develop presets (both colour and B&W) included in Lightroom 4. However, when I updated to Version 6.9 the colour presets disappeared and I can't find them anywhere. When I go to Preferences, the Lightroom Presets folder within Develop Presets shows empty despite only the Colour Presets being missing in the side panel on Lightroom. I note that other members of this forum have had similar problems but not quite the same as mine (e.g. all their Develop Presets have disappeared not just Colour Presets).
A solution to my particular problem would be appreciated, noting I'm only semi computer literate.

