Default cache location
By default, the Opus thumbnail cache (if enabled at all) is stored on your system drive.
Moving the cache by hand
If you wish to move the cache to another drive you can do so by creating a directory junction which diverts the standard location to somewhere else.
(This only works if your system drive is formatted as NTFS, but that is almost always the case these days.)
Button to automatically move the cache
Here is a button which automates the process. When you click it you will be prompted for the new cache location. The button will move the cache (into a sub-folder named Thumbnail Cache) and create the junction for you.
Note: The first time you use the button it will move the cache but if you use it again it will copy the cache. So if you change the location twice you will need to delete the extra copy of the data.
See How to add buttons from this forum to your toolbars for what to do with the block below.
<?xml version="1.0"?>
<button backcol="none" display="both" label_pos="right" textcol="none">
<label>Move Thumbnail Cache</label>
<icon1>#makedir</icon1>
<function type="normal">
<instruction>@nofilenamequoting</instruction>
<instruction>@Set dd={dlgfolder|Select new thumbnail cache location}</instruction>
<instruction>Copy MOVE "/dopuslocaldata\Thumbnail Cache" TO "{$dd}"</instruction>
<instruction>Copy MAKELINK=junction "{$dd}\Thumbnail Cache" TO "/dopuslocaldata"</instruction>
</function>
</button>
(Updated 15/Mar/2011 to fix an issue with spaces in the parent of the target path.)