HMessage : Macros are disabled because the secirity level is set to High. To
run the macros, lower the security setting and verify the marcos are signed
and trusted.

Problem is that this only happens when I open one specific worksheet (not
any others). Also, I never use macros. If I go into tools, there are no
marcros installed. Virus checked file - no bugs. ,,,,,, .....

I just click OK and go on using worksheet.

Any knowledge as to why would be appreciated.