I am not using a third-party template, just the default powerpoint blank template.

I tried creating a new text box as suggested; it wrapped downward after each letter. Wrap text was checked so I unchecked it. The box then extended to the right with no wrap. I right-clicked and selected "set as default" then created a new text box. It again wrapped down after each letter. When I checked format, I found that wrap text was checked. Apparently the "set as default" function does not include the wrap text option.

I had time for some experimenting today. First, I moved a ppt file to two other computers, one running Windows 10 with office 2013 (same as the computer on which I first noticed the problem) and the other running Windows 7 with office 2013. The second Win-10 computer exhibited the same behavior as the first; default status for text box is with wrap text checked and the letters wrap down one by one. On the Win-7 machine, though, the default text box does not have wrap checked, and the text fills to the right. This is true for new, blank ppt files, and for the ppt file moved from the Win-10 machine.

The behavior on all three computers is the same whether I use an existing ppt file, or open a new file to the default blank template, so does not appear to be related to any individual ppt file. I also tried the experiment with an old ppt file that I created in the distant past and have not modified since 2005 (although I'm not sure which version of powerpoint I was using back then). The default text box in that file also has wrap checked when opened on the Win-10 computer.

One other oddity I noticed on the first computer. When I reboot the computer and open powerpoint from the start menu, the first text box I create will not wrap. However the second text box, and all subsequent text boxes, will wrap. Closing and re-opening powerpoint does not help - even the first text box will wrap. However, rebooting again will reset the system somehow so that the first box will not wrap but the second will. This behavior, however, applies only to one of the Win-10 machines - the other always wraps, even on the first text box after reboot.

Both of the Win-10 machines also have a default size for new graphics objects of 0.05 inches (about 1 mm). The Win-7 machine has a default size of 1 inch.

So maybe the problem is with the operating system rather than the powerpoint version?

Any help is appreciated.

Thanks.