Hi,
>1. check if a specific file exists or not.
In addition to what Tracy already suggested, you might also consider to use SYS(2000, "c:\somefile.txt"). The advantage of this function in contrast to FILE() is, that SYS(2000) only looks in the path you specify in the parameter. FILE() looks for the file along the path you've set in VFP with SET PATH TO ...
HTH,
Armin