Excel 2003

I have VBA code stored in an .xlA file (not installed as an 'AddIn' in Excel); the code opens up an .xlS file and does a lot of data manipulation and importing data from other files; at one point, it opens an .xlT file (there is code stored in 'ThisWorkbook' module using 'BeforeSave' Private Sub). A specified worksheet is copied from the workbook that was 'Active' immediately prior to opening of the .xlT file to the .xlT file; then, a 'SaveAs' command saves the modified .xlT file as an .xlS file with a new filename. At this point in time, the spreadsheet becomes 'invisible' (only reference on Taskbar is VBA code), although it is still open (I am using two monitors to step thru the code; VBA on the right monitor and spreadsheet on the left monitor.).

The macro continues to process code correctly, but can someone explain this behavior.

Thanks for a response,

Chuckles123