Thanks for getting back to me!
I tried adding the 's' to http in front of cellar.org but, unfortunately, that didn't help when I tried a couple of minutes ago.
The image I was attempting to upload is in My Docs.
Please forgive my brevity but I'm in the middle of preparing lunch and just dashed in here for a quick look!
ETA
I've just had a further attempt at adding 's' after http and I've been able to post an image!
As noted, I was a bit rushed in my previous attempt so perhaps attention to detail suffered.
BTW, it's Post #247 in the 'Horses' thread.
I think that you have hit the nail on the head, Clod. Many thanks!
Further edit:
I've just looked at my Bookmarks and found that the address for the site lacked the 's'.
I've now amended it to
https://www.cellar.org/ so with luck the problem won't manifest itself again!
Thank you for your forbearance of my ineptitude.