I want to insert some text, a custom property field and some other text in an existing bookmark.

Can anyone give me an example how to solve this

I'm sure there will be a more elegant way to do this but this is my first attempt

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Andrew Lockton
Chrysalis Design, Melbourne Australia

Andrew showed you how to insert the DocProperty field for the built-in property "Title" and apply a bookmark to it. The same method would work with a custom document property.

I am unsure. When you talk about a "Custom Property" what, exactly, do you mean? Where and how is that property established?

@Guessed :
Your sollution extends the field with the text that is inserted after the field.

I tried if a range.collapse after range.end=field.result.end, but that gave the same result

any sugestions?

this is what will work:
.Fields.Add(Range:=YourRange, Text:="DOCPROPERTY ""Your DocProperty""")

With a small change to the code it worked;

Sub DemoReplaceBookmark()
Dim aRng As Range, aField As Field
Set aRng = ActiveDocument.Bookmarks("aaa").Range
Set aField = ActiveDocument.Fields.Add(Range:=aRng, Text:="DOCPROPERTY ''"Title with spaces""")
aRng.InsertBefore "text in front"
aRng.End = aField.Result.End + 1
aRng.InsertAfter "text at end"
'aRng.Select
ActiveDocument.Bookmarks.Add Name:="aaa", Range:=aRng
End Sub