Please press the Control key on your keyboard and use the mouse cursor to resize the thumbnails to icons in the "Open file" window.
Let us know if that helps.
Thanks for your response Akash, but it is not the size of the icons that is the issue, it is that they are spaced wide apart in the window, when they used to be close together. I have fully explored the menu you mentioned by right clicking within the "open" window. (Ctrl does not work on my keyboard since Win 10 even though I have it enabled). At the moment I have large icons selected and I have made the window as large as possible. I can see 6 icons without scrolling. It is the space between the icons that I want to eliminate.
Could you please provide a screenshot of what you're seeing?
Will do, when I am home on Monday.
Previously, before the last Win 10 update, there was almost no blue to the left or right of the icon (when I hover my mouse over the icon), and the file info underneath always word wrapped so the text was never wider than the icon itself. I used to see 4 icons across this size window, and the next row underneath was very close to the row above, now there is a lot of space between the rows of icons.
No other picture viewer on my PC has changed how it displays pictures. As I said, it is just a minor but irritating thing that has changed.