Hello superfit00 and welcome to the forums!
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Try this:
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In OpenLP:
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Open the "Tools" menu, click "Open Data Folder..."
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This opens the location where your data is stored.
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In there, you will find "custom" folder and inside that there is a file called custom.sqlite
This is where your custom slides are stored, copy it to an another location, then update to Windows 10.
After that, you should be able to copy the old custom.sqlite file to your OpenLP data folder in Windows 10.
(Please don't do this while OpenLP is curently running.)
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Since you are using OpenLP version 2.0, you should update to version 2.4.1 if you
are not using transparent themes, and to version 2.2.1 if you are.
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I hope this helps,
all the best and welcome once more,
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Azaziah
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