Reuse images

gmj12345 Please read my first response carefully. First time you have to upload a image using "From Computer" option.

Then you can reuse it using "From SharePoint" or "From Address" options.

But seems like "From SharePoint" option is not available for you for some reason so you will have to use the "From Address" option.

On "From Address" popup, you have to use the previously added image URL in "Address" field.

Now, to get the previously added image URL:

1. Check my first response to understand where the previously added image is stored in SharePoint. It will be at location like: Destination Library selected > SitePages > Page Name folder
2. Go to the folder as mentioned in step #1. Then you have to get the direct URL of the image. Which you can get using Copy direct link option in library, full the steps mentioned here:  Uploading files in SharePoint 
3. Use the image URL in "Address" field on "From Address" popup while adding image to wiki page.

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