Take a look a Measure Attributes for that measure. You will see the place to add more space at the beginning.

Yoshihiko Katori,

When I look at you screen shot, I get another thought:

Try applying Music Spacing, and Update Layout.

My guess is that {Music Spacing + Update Layout} will make room for the accidentals.

Thank you Mike and Peter. Measure attributes resolved the problem but I have to check and edit each measure. Music spacing, I made arrange the preference as much as possible, but it doesn't work. Before I realized this problem, it was all OK even without any arrangement of Music spacing. So I don't understand why it happens.

Try different kinds of music spacing to see what looks best to you. Select all with the selection tool (ctrl+a), and on Windows, ctrl+4 is note spacing while ctrl+5 is beat spacing.

It's been resolved.

"Document Options>Acccidentals>Adjustment at Start of Measure" should be "0". I don't remember why I changed this to "minus" digit.

Thank you.

That'll do it.