XL: "Formula Contains an Invalid External..." Referring to Sheet

• Microsoft Excel 97 for Windows
• Microsoft Excel 98 Macintosh Edition

SYMPTOMS

When you enter a new formula or edit an existing formula in a Microsoft Excel worksheet, you may receive the following error message:

   Your formula contains an invalid external reference to a worksheet.

   Verify that the path, workbook, and range name or cell reference are
   correct, and try again.

CAUSE

This problem occurs when you enter a formula that refers to a worksheet with a name that contains a left bracket ([) or right bracket (]) character.

WORKAROUND

To work around this problem, remove the bracket character from the name of the worksheet that you are referencing in your formula.

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

The following characters are not valid characters to use in worksheet names:

   \
   /
   ?
   *
   [
   ]

REFERENCES

For more information about renaming worksheets, click the Index tab in Microsoft Excel Help, type the following text

   renaming, worksheets