I have a macro that writes a formula in the worksheet that links to
another worksheet. So the VBA code looks something like this "='C:
\PROJECTS\[OtherWorkbook]Sheet1'!A1". The macro is working, but if
somehow I define the address wrong, Excel then pops up the Explorer
form asking me to find the "correct" file. Is there an error trapping
code that I can use in my macro to stop the macro BEFORE the Explorer
form comes up, so that I can have my own MsgBox pop up and then end
the macro run?

Many thanks!