Alan,
Donot store anything in GeneralFields, and if you must than donot.
I don't. The original questioner did.
Just store the fullpath in of the .doc .xls or whatever file in your memo field.
I generally store a relative path beneath a defined root location and retrieve files when needed as root location + relative path.
Storing a full UNC path or (shudder) path with a drive letter is a bad idea because you'll have to re-path everything when the server changes or the data\external files are otherwise moved, or file shares change. If you do it the way described above you only have to change the root location definition in one place.