I apologize Andre. I did not intend to be rude or disrespectful. I am still learning about all these things. I found the Admin Tools, and I found how to use the "Update thumbs and/or resize photos" feature. Once I understood as much as I could, it seemed to me like this was going to perform that action on all the images in that album. Since it was only 2 images that were affected, and since this member is a good friend, it seemed to me simpler to ask him to delete them and re-upload them, rather than perform the "update" on all the images in the album.
So in the end, I have learned from your advice, and made use of your considerable skills and experience, that you kindly shared in this topic. Using what I have learned from you, I was able to make a decision about what to do. Just because I didn't choose your method should not be seen as a snub. Now I know what to do if I inadvertently change one of those settings in the future (when no doubt, there will be many more than just 2 images affected). I thank you for your support
I don't know what to say (or do) about your well-intentioned comments about my server configuration. I fully realized they are based on knowledge and experience that is far more advanced than mine. If I understood why it matters that there is a server error on folders (dirs) which are not webpages at all; and why they are supposed to show blank pages instead; I would be in a better position to discuss it with my webhost. I hope you understand that I can't keep telling them -- "somebody said this is wrong" without being able to discuss with them why it's wrong. I mean, for example, if I posted a message in this forum, that said, "somebody told me something is wrong with the way the galley is coded - I want you to fix it"; you would probably reply with some not-so-nice comments, right?
As I said before, if you were willing to explain it to me, or perhaps refer me to articles, or something like that, I am just SO happy to learn as much as I can about it. But without some knowledge or understanding about server config and server management, I really have to trust that my host knows what they're doing. (And again, I do understand that you don't provide server support.)
Niecher, actually I didn't delete the files. Since that member is a good friend, I asked him to re-upload them. I'm a bit puzzled why he deleted, but hasn't re-uploaded yet. Perhaps he was on his phone, or didn't have the flash drive with him, or otherwise couldn't access the images at the time when he received my PM. I'm sure he will upload them as soon as he can. No worries about that.
However, I appreciate your instructions for me to replace them myself. I can see where that plug-in would be very useful -- especially for a newbie like me!!
I think we have communicated very effectively, Niecher. I have understood your messages, and know that you want to be helpful. And I very much appreciate your efforts and the time you've devoted to help me with my gallery! Thank you very much!
All best