Paris a an interesting place to visit.
The file IMG_2202.JPG
looks fine from here although the subject matter is blurred due to zooming in to try and see the people on the bridge which has made your image too big for displaying and serving to the Internet.
All the thumbs displayed fast and all were intact with no problems. So your server is working just fine and you need to look elsewhere for the solution. All the images referred to in the thumbs had a size too big for serving to the internet or displaying properly on web pages. This will cause issues in some browsers.
Reduce the resolution of the file as it is really too big for the Internet.
The size is 1600px x 1200px
Try and compress it to 75% and reduce the physical dimensions to say no larger tha 800x600.
All your visitors to your web site will not have broadband and will not wait for the images to load before they are gone.
Also it would entail scrolling on most of your visitors screens who don't have a screen resolution of 1600x1200 or don't use their browser in full screen mode.
A helpful tutorial:
A Goole search: