error code while opening a workbook
 

I keep getting an error code when opening a workbook (whether manually
or via VBA). It says "Problem during load" and then it shows two file
names--the path is the same as the path for the file I'm opening and
then each of the two files in the error message have this appended to
the path:
\css\ldi.css
\css\style_ldi.css

FYI this only happens with workbooks that have stuff copied and pasted
from a specific website, with zillions of hyperlinks and weird
formatting, tables etc. in the source material.
What should I do?
Thank you very much!!!!!