Characters.Insert method (Excel) is misleading. The Insert method doesn't insert; it actually replaces and should be called the Characters.Replace method. However, if you really want to insert use this:
v = Range("A1").Characters(12,0).Insert("day") to get the result:
Now is the daytime for you.
To summarize: Range(...).Characters(Start, Length).Insert actually replaces Length characters beginning at Start; use zero Length to insert.
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