Question

I have full admin privileges on my Windows 7 machine but when I run my application which creates a file on c:\ drive I get error code 5 (Access is denied). I know windows 7 doesn’t allow creating files in protected areas like c drive and program files and file explorer brings up ‘administrative’ message box if I copy a file there from somewhere else after which it does allows but can my application obtain write level access?

In my application, user gets to pick the folder where they want to create the file so if they choose c:\ drive s/he will obviously get this error which is not desirable.

void CTestDlg::OnBnClickedButtonCreate()
{
    CFile f;
    CFileException e;
    TCHAR* pszFileName = _T("c:\\test.txt"); // here i am hard coding path for simplicity.
    if(!f.Open(pszFileName, CFile::modeCreate | CFile::modeWrite, &e))
    {
        TRACE(_T("File could not be opened %d\n"), e.m_cause);
    }

}

As far as I have researched it seems I can’t by-pass the UAC dialog which is fine but my application don’t even present it (which is understandable as well) but what are my options?

I see my only option is to detect this in my own application if this is Windows 7 OS and than check for file path before creating the file and present a more user friendly message ‘windows 7 doesn’t like you to create file in this folder, choose a different folder or go back to xp’. Is this scheme the way to go on Windows 7? Is there any other way?

Answer 1

As Kolink noted, your application needs to run with administrator privileges. In order to do that automatically, embed a manifest as explained here.

EDIT: For VS2010: Project Properties > Configuration Properties > Linker > Manifest File Change the ‘UAC Execution Level’ to the desired value.