You receive a "This file is locked" error message when you try to save or close a shared file

CAUSE

This behavior may occur when the shared workbook is open in Microsoft Quick View or when you are attempting to save the workbook while another user is opening the file in Microsoft Excel.

Case 1: The Shared Workbook Is Open in Microsoft Quick View

This behavior occurs if the file you are saving or closing is open in Microsoft Quick View. Quick View is a program that is included with Microsoft Windows 98. Quick View allows you to view a document without opening it in the program that was used to create the document. When you open a nonshared file in Excel, you cannot open the same file in Quick View because the file is locked by Excel. However, when you open a shared file in Excel, the file is not locked (to allow sharing), and you can view it in Quick View. When you save or close a shared file in Excel, Excel locks the file for saving. If you save or close a shared file in Excel while the file is open in Quick View, you receive the error message in the "Symptoms" section because the file is locked by Quick View in this case.

NOTE: If you open a shared file in Excel, set the file attributes to read-only (from the folder window that contains the file) while the file is still open, and then save or close the file, the error message appears.

Case 2: Another User Has Opened the Shared Workbook

This behavior occurs when you save a shared workbook and another user has already opened the workbook. The error message may also appear if you share a file while another user is opening the file because sharing a file requires that you save it.