Media Library — some images missing thumbnails; some medium-size images missing

I am running into this on seven websites. Some images are suddenly not displaying on pages. If they have captions, those show but not the image. I checked the Media Library and some are missing the thumbnail. Some images are just missing but the Title and Alt information is still there so they aren’t missing because I deleted them–the image file is just gone from the Uploads folder. (For example, see https://botanical-art.baeecorp.org/lecture-by-mary-page-hickey/)

The missing thumbnails had happened a few months ago after a WordPress update and I found a plugin that can regenerate them. I activated the plugin and ran it on the Library. Some of the missing thumbnails were repaired and it listed all the images that were in the Library that can’t be found now (between 8 to 27 images per website). The websites are on three different hosting services.

Some of the missing images are the ones WordPress generated for the Medium size. I’ve checked several images in the Library and some still have the medium size but others have disappeared.

I don’t understand why this is happening but I’d like to know how to recreate the Medium sizes. I could use PhotoShop to make a new one at the specific size and give it the old name but when I upload it (Add New), WordPress will then generate three to four smaller versions of it that I don’t need filling up my Uploads folder.

Is there a way to replace the missing images with new ones of the same name given it by WordPress for the medium size without having more created from it? Would just using FTP to replace a missing file work since the data for it is still in the Media Library?

Thanks.

• This topic was modified 7 years, 6 months ago by sleeplessindc. Reason: Added additional question

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