VBA Excel Paste to PowerPoint in Bold

Question

Applying formatting to substrings is not difficult, but it can be cumbersome given the depth of PowerPoint's object model. Here is a simple illustration.

NOTE I modified the string concatenation because it looked incorrect to me (essentially you were duplicating the string within itself, which didn't seem correct).

Sub Main()
'This will be the calling procedure, so it can be the one which
' builds the concatenated string, but also will be where you define
' which parts of this string should be bold
Dim str$
Dim boldWords as String

'Establish a string of words/phrases to bold, to be used later
boldWords = "Release Date,Distributor,Genre,Starring"

'Create your concatenated string
' I modified this because I don't think it was correct
str = ""
str = "Release Date" & str & objWorksheet.Cells(i, 1).Value & Chr(13) & _
    "Distributor" & objWorksheet.Cells(i, 2).Value & Chr(13) & _
    "Genre"  & objWorksheet.Cells(i, 10).Value & Chr(13) & _
    "Starring" & objWorksheet.Cells(i, 7).Value & Chr(13) & Chr(13) & _
    objWorksheet.Cells(i, 14).Value

'Put these words in a shape:
ActivePresentation.Slides(1).Placeholders(1).TextFrame.TextRange.Text = str

'Send your string, the list of bold words, and the shape in to a subroutine
'  that will apply the bold font
BoldSomeWords ActivePresentation.Slides(1).Shapes(1), str, boldWords

That subroutine will then invoke the following sub, which applies formatting bold for particular substrings, given as part of the list assigned in myWords variable, above.

Sub BoldSomeWords(shp As Object, str As String, myWords As String)

    Dim word As Variant
    Dim iStart As Integer, iEnd As Integer

    'Convert the list of words in to an iterable array, and
    ' iterate it.
    For Each word In Split(myWords, ",")
        'Loop just in case there are duplicates, or omit the Do Loop if
        ' that is not a concern.
        Do Until InStr(iEnd + 1, str, word) = 0
            iStart = InStr(iStart + 1, str, word)
            iEnd = iStart + Len(word)
            shp.TextFrame.TextRange.Characters(iStart, Len(word)).Characters.Font.Bold = msoTrue
        Loop
    Next

End Sub

UPDATE FROM COMMENTS

I changed the declaration for shp in the BoldSomeWords routine to generic object instead of Shape. I think there is a conflict between a PowerPoint.Shape and an Excel.Shape, and in the context of your VBE, it assumes to be an Excel.Shape, hence the mismatch.

Either of the following should work, late-binding as generic Object:

BoldSomeWords(shp As Object, str As String, myWords As String)

Or early-binding as a strongly-typed shape:

BoldSomeWords(shp As PowerPoint.Shape, str As String, myWords As String)

A few more things to consider...

Get rid of New keyword in your objWorkbook declaration, it's unnecessary because you're assigning the objWorkbook using the Excel.Application.Workbooks.Open method, so you don't need a New workbook.

Change PPT from generic Object to strongly typed PowerPoint.Application there is no real reason to mix early- and late-binding your objects.

You have three assignment statements Set PPT = GetObject(, "PowerPoint.Application"). Only the first one is needed.

Declare ALL of your variables, sPath, sFile, i... There may be more, if you use Option Explicit that will identify the undeclared variables for you.

There were one or two places where you used the fully qualified PPT.ActivePresentation.Slides(PPT.ActivePresentation.Slides.Count) when you already have a variable pptNewSlide. Use this for brevity's sake, instead, for example in the last two lines, you could change to:

pptNewSlide.Shapes(1).TextFrame.TextRange.Text = str

BoldSomeWords pptNewSlide.Shapes(1), str, boldWords