C2664 showing up only in release configuration

Question

I'm trying to build a program for release, but even though it works fine in a debug configuration, I am getting this error when I use the release configuration:

1>c:\users\owner.ben-pc\documents\visual studio 2010\projects\xsp quick unpacker\xsp quick unpacker\Form1.h(217): error C2664: 'DeleteFile' : cannot convert parameter 1 from 'const char *' to 'LPCTSTR'
1>          Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast

I tried adding the "#define _SECURE_SCL 0" line as per this thread, but that didn't change anything.

Here's the part of the program that the line that is throwing the error is in (the "DeleteFile(temp);" is the specific line that throws the error):

path=this->FilePathBox->Text;

            if (!File::Exists(path+"\\filemaker\\start.ini"))
            {
                FileStream^ fs=File::Create(path+"\\filemaker\\start.ini");
                delete fs;
            }
            else
            {
                marshal_context^ context=gcnew marshal_context();
                String^ filepath=path+"\\filemaker\\start.ini";
                const char* temp;
                temp=context->marshal_as<const char*>(filepath);
                DeleteFile(temp);
                delete context;
            }

P.S. I'm using VS 2010 Premium.