COMMUNITY SOLUTIONS CONTENT DISCLAIMER
They may look like:
or anything else. Often those names contain non-printable characters.
But there may be other causes too, including a partial corruption of the workbook that contains the defined name.
Here are the steps involved:
1. Select Tools, Options and click the General tab.
2. Click the check box next to "R1C1 Reference Style", so that you change the current setting.
3. Press OK.
4. Excel will prompt you to change the name of any name (in all open workbooks!) that contains illegal characters.
5. Select Insert, name, define to delete the newly renamed names.
6. Set the R1C1 Reference style back the way you prefer using Tools, Options, General.