To convert a string from ANSI to Unicode use the function "MultiByteToWideChar", give it "CP_ACP" code page, the string you want to convert, its length and a buffer where to put the resulting string. Once you have the string, pass it to "IsValidURL" function to do the work you want.
If you still cannot do it, ask me so I will try to code it for you, but don't think it will be rapid, I have many things to do also.
Nice day!
He who never make mistakes, makes nothing...