Then why does some online info say up to 24 items are retained in Clipboard history -- and even the Clipboard in Word displays this. Seems like sometimes I can see multiple images (history) and sometimes only 1. What are the rules?
If your getting this online - Check Active X Components - If your constants, logged in to MSN, or you use both on and Offline Office. This is a possible reason. The Component maybe in your IE addons - Named Research: Or OCOW~11 for older Office editions
or possibly something else. Newer could be like: Office document cache handler.
You can also check other browser extensions and read the data to see if it records such history. Manage Addons, Click the file you wish to check in the list, then more Information in the bottom section. With the option to disable the addon.
If you can not see where the addons located and wish too
Go to addons, Right Click the any of the Name tabs for the Columns and tick all the boxes so you can find if, its something you did, something that came preconfigured or has just been left without knowledge till now.
Also on your Desktop version of Word Check the Edit Section of clipboard
Untick anything that suggests Auto Collection. Its highly possible that it could be something totally different but these areas are where you would look to start to Isolate, if at the least point you in the right direction to the culprit on your system.
As regards "What Are the Rules" Honestly the answer could be as broad as you asking those 4 words. Consider : OS, Version And Build, Office Version & Build, Browser plugins and additions., 3rd Party applications that utilise the clipboard. System configuration,
Settings and so on.
Regards
Example Screens
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