This is not a malfunction, but a matter of user preference. In nearly all
versions of Microsoft Office-Word, if this is what you're using, you can
select "Single" line spacing. This will appear in your line adjustment
shortcut, at the top or bottom of your screen, within your Microsoft
Office-Word program. If you have a difficult time locating it, go to your
Toolbar options Drop-down menu, and add a checkmark to the "line-spacing"
option. It will appear, as a floating taskbar, that you can drag and add to
the rest of your shortcuts. If for some reason, this method does not work,
go into the Editing dropdown menu, and you will find the same option there.
The 1.5 is just one of many options, but is not conclusive or symptomatic of
any type of corruption. Single line spacing is usually available by default,
and someone might have unknowingly, by accident changed the default. Just
restore the default, in your editing options. Please let me know if I
missunderstood the question.

"Samuel via OfficeKB.com" wrote:

I encounter a special document which single line spacing appears as 1.5 line,
even the paragraph setting say so. The vertical alignment is Top.
After changing the fonts, the problem still persists.

If ctrl+A then copy to a new document, the problem still exists. The problem
disappears if the last mark in the document is NOT copied. What is the
problem? help!

The boss owns this document wants to know the cause..., not only the solution,
help!