Slow running worksheet macro

Turn off some of Excel's functionality before running code and turn on afterwards:

Sub test()
With Application
  .Enableevents = False
  .displayalerts = False
  .ScreenUpdating = False
  .DisplayStatusBar = False
  .Calculation = xlManual
End with

' Your code goes here

With Application
  .Enableevents = True
  .displayalerts = True
  .DisplayStatusBar = True
  .Calculation = xlAutomatic
End with

I suspect that your code is self-triggering itself because Enable events is turned off.

abousetta

Hello Phil Payne,

I agree with stnkynts, and the all I can suggest is to try the Code as amended below.

Option Explicit
Private Sub Worksheet_Change(ByVal Target As Range)

' This code checks for a change of Status in the Current Status column and
' on change sets (adjacent) cells' 'interior' and 'font ' colours according to table "rCodes".

    Dim rCell As Range
    Dim rCodes As Range
    Dim rRow As Range
    Dim vMatch
    Dim LastRow As Long

Application.ScreenUpdating = False
Application.Calculation = xlCalculationManual

    If Target.Count > 1 Then Exit Sub

    LastRow = Range("A65536").End(xlUp).Row
    Set rCodes = Range("g6:g16")

    If (Target.Column >= 1) And (Target.Column <= Range("D1").Column) And (Target.Row <= LastRow) Then
        If Len(Target.Value) > 0 Then
            On Error Resume Next
            vMatch = Application.Match(Target.Value, rCodes, 0)
            If IsError(vMatch) Then
               'DO NOTHING
            Else
                With Target.Cells
                     .Offset(0, -1).Interior.Color = rCodes.Cells(vMatch).Interior.Color
                     .Offset(0, -1).Font.Color = rCodes.Cells(vMatch).Font.Color
                End With
            End If
        End If
    End If
    
Application.Calculation = xlCalculationAutomatic
Application.ScreenUpdating = True

End Sub

@ Thalassa,

Thank you for reporting this infringement of Forum Rules.

@ Phil Payne,

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