VBA conditional searching for entire cell contents

[Time2Learn]

I am trying to write a VBA module to help me identify the source of an excel file that I am given based on known cell values in the header. For example if ""Service Waiver Acknowledged"" exists in any position of the range A1:Z5 then I know this file came from Software1 whereas if ""AnnivDay"" exists in any position of the range A1:Z5 then I know this file came from Software2. I know this because those are unique cell values that do not exist from any other software source in my sample. I was originally doing this:

Range("A1").Select
ActiveCell.FormulaR1C1 = _
        "=IF(AND(RC[1]=""Last name"",RC[2]=""First name"",RC[12]=""Last Seen"",RC[14]=""""),""Software1 List"","""")"
    Range("A2").Select

the problem with this is someone may have done formatting and moved these columns around or removed one, which would make this fail and not show any result.
Next I tried something like this:

Dim rng As Range

Set rng = ActiveSheet.Range("A1:Z5")

For Each cell In rng.Cells
   
    If InStr(1, cell, "Last Seen") > 0 Then
        MsgBox ("Software1")
   ElseIf InStr(1, cell, "Last Seen Date") > 0 Then
        MsgBox ("Software2")

The issue here is that Software2 uses ""Last Seen Date"" so this code will not accurately identify ""Last Seen Date"" as Software2.

I've been having trouble finding a good solution for this as I am relatively new to VBA and my googling hasn't provided a good solution.

This is what I'm looking for and I'm sure I'm just not using correct phrasing
If an entire cell contents ""LastSeen"" appears in A1:Z5, then MsgBox ("Software1")
then I can continue that logic with the ElseIf statements for my list of unique identifiers.

Thank you for any suggestions, including how to better post here as this is my first time posting, long time lurker.

 

[Time2Learn]

​

Why not using a 'Settings' worksheet rather than hardcode arrays ?​

I'm not familiar. would that help me identify those unique header cell entries?

 

[Marc L]

​

'Settings' worksheet : in column A the key words to identify a software and in column B the software names accordingly …​

This worksheet must be 'sorted' from the most common key words to the less common and special cases before usual cases.​

If the key 'Last Seen Date' identifies a different software than 'Last Seen' so it must be in the list before 'Last Seen'.​

If a software can be identified by 'Last Seen' like by 'Last Seen Date' so the list can contain a single key as 'Last Seen*'.​

Using this worksheet avoids to maintain the code …​

 

[Time2Learn]

​

'Settings' worksheet : in column A the key words to identify a software and in column B the software names accordingly …​

This worksheet must be 'sorted' from the most common key words to the less common and special cases before usual cases.​

If the key 'Last Seen Date' identifies a different software than 'Last Seen' so it must be in the list before 'Last Seen'.​

If a software can be identified by 'Last Seen' like by 'Last Seen Date' so the list can contain a single key as 'Last Seen*'.​

Using this worksheet avoids to maintain the code …​

Thank you for giving me another possibility to look into