You can set image creation to something else than "on upload" - e.g. to Always if it doesn't exist

Thanks, but this is exactly what I mean. I set it to "always" and then I have to open and save every of my +1000 articles by hand so the thumbnails get rebuilt. I need a button that rebuilds all thumbnails for all articles in a category in one go.

Hi,

you don't need to open and save those articles, thumbnails will get created when article is viewed. eg. when google bot opens it.

But if you really need to force thumbnail creating I would suggest you create a new search & list of that category and put thumbnail on the list, this way multiple thumbnails will be generated in one go. i would also suggest you use "always if not exists" as this way thumbnails get generated only once.

Thank you for the quick response and the solution. The list methode regenerated the thumbs in most cases, some did not get rebuilt, no clue why.

Hi,

it could be you are hitting some server limitation, image resizing is very resource intensive process.