|To add to AlteK's suggestion, I think this will work, but I don't have time to test it.|
In the workbook that you are monitoring, set a cell that is linked to the cell in the Counter.xlsm file that stores the count. It should reflect the current value in that cell when you open the workbook that is being monitored. It won't save the value if the file was opened read only, but that shouldn't matter since it will be updated the next time the file is opened.
You might need to add an Application.Calculate instruction at the end of AlteK's code so that workbook calculates and reads the updated cell in the Counter workbook after it has been saved.
As I said, this is untested.
Click Here Before Posting Data or VBA Code ---> How To Post Data or Code.