Reduce Macro Time - excel

Question

I have been worked on a VBA code for past couple of days and everything seems to be working fine till one fine day when I added the below code to it. It marco executed time increased to such an extent that I myself don't when it is going to complete. I have waited for almost 2 hours but it continues to run.
This datasheet that I have is about 15 MB in size and contains around 47,000 rows with 25 columns filled with data. I have running this code to delete rows basis the multiple criteria on Columns "H".
Here is the code. Any help to reduce the runtime is highly appreciated.
Thanks...
Application.ScreenUpdating = False
Application.EnableEvents = False
Application.Calculation = xlCalculationManual
Application.DisplayStatusBar = False
Workbooks("Vivar_Template_Blank.xlsx").Sheets("Main & PCO Working").Activate
Dim ws As Worksheet, i&, lastRow&, value$
Set ws = ActiveWorkbook.ActiveSheet
lastRow = ws.Range("H" & ws.Rows.Count).End(xlUp).Row
For i = lastRow5 To 2 Step -1
value = ws.Cells(i, 8).value
If Not (value Like "*Supplier Name*" _
Or value Like "*[PO]Supplier (Common Supplier)*" _
Or value Like "*ACCENTURE LLP*" _
Or value Like "*COGNIZANT TECHNOLOGY SOLUTIONS US CORP*" _
Or value Like "*INFOSYS LIMITED*" _
Or value Like "*INFOSYS TECHNOLOGIES LTD*" _
Or value Like "*INTERNATIONAL BUSINESS MACHINES CORP DBA IBM CORP*" _
Or value Like "*MINDTREE LIMITED*" _
Or value Like "*SYNTEL INC*" _
Or value Like "*TATA AMERICA INTERNATIONAL CORPORATION*") _
Then
ws.Rows(i).Delete
End If
Next
Application.EnableEvents = True
Application.ScreenUpdating = True
Application.Calculation = xlCalculationAutomatic
Application.DisplayStatusBar = True

Answer 1

Or is not short-circuited so each Like expression will be executed, an alternative to halt on the first match (you don't actually need Like in this case, you can use the more efficient InStr):
Dim lookup(9) As String
lookup(0) = "Supplier Name"
lookup(1) = "[PO]Supplier (Common Supplier)"
lookup(2) = "ACCENTURE LLP"
lookup(3) = "COGNIZANT TECHNOLOGY SOLUTIONS US CORP"
lookup(4) = "INFOSYS LIMITED"
lookup(5) = "INFOSYS TECHNOLOGIES LTD"
lookup(6) = "INTERNATIONAL BUSINESS MACHINES CORP DBA IBM CORP"
lookup(7) = "MINDTREE LIMITED"
lookup(8) = "SYNTEL INC"
lookup(9) = "TATA AMERICA INTERNATIONAL CORPORATION"
For i = lastRow5 To 2 Step -1
value = ws.Cells(i, 8).value
For j = 0 To UBound(lookup)
If InStr(Value, lookup(j)) Then
ws.Rows(i).Delete
Exit For
End If
Next
Next
If any values are empty or there is a large distribution of a constant non-matching value, you should check and exclude them first.

Answer 2

Deleting Rows (Row by Row) is slow , try to use Union and delete all Rows by one time.
Application.ScreenUpdating = False
Application.EnableEvents = False
Application.Calculation = xlCalculationManual
Application.DisplayStatusBar = False
Workbooks("Vivar_Template_Blank.xlsx").Sheets("Main & PCO Working").Activate
Dim ws As Worksheet, i&, lastRow&, value$
Dim uRng As Range
Set ws = ActiveWorkbook.ActiveSheet
lastRow = ws.Range("H" & ws.Rows.Count).End(xlUp).Row
For i = lastRow5 To 2 Step -1 ' !!! maybe lastRow not lastRow5 because there is no value for lastRow5 in your code!!!
value = ws.Cells(i, 8).value
If Not (value Like "*Supplier Name*" _
Or value Like "*[PO]Supplier (Common Supplier)*" _
Or value Like "*ACCENTURE LLP*" _
Or value Like "*COGNIZANT TECHNOLOGY SOLUTIONS US CORP*" _
Or value Like "*INFOSYS LIMITED*" _
Or value Like "*INFOSYS TECHNOLOGIES LTD*" _
Or value Like "*INTERNATIONAL BUSINESS MACHINES CORP DBA IBM CORP*" _
Or value Like "*MINDTREE LIMITED*" _
Or value Like "*SYNTEL INC*" _
Or value Like "*TATA AMERICA INTERNATIONAL CORPORATION*") _
Then
'ws.Rows(i).Delete
If uRng Is Nothing Then
Set uRng = ws.Rows(i)
Else
Set uRng = Union(uRng, ws.Rows(i))
End If
End If
Next
If Not uRng Is Nothing Then uRng.Delete
Application.EnableEvents = True
Application.ScreenUpdating = True
Application.Calculation = xlCalculationAutomatic
Application.DisplayStatusBar = True

Answer 3

You could build a set of nested if/else constructs such that your logic terminates when the first true condition is encountered.
If Not (value Like "*Supplier Name*") then
ws.Rows(i).Delete
else if value Like "*[PO]Supplier (Common Supplier)*" then
ws.Rows(i).Delete
else if ...
End If
After you do this, another level of optimization would be to order the 'if' statements from most prevalent to least, thereby reducing the number of expected comparisons.