You are probably right. If you want to have EVERYONE permission, you need to create new security descriptor. NULL says that the default ACL is used, i.e. only the user or someone with higher privileges (administrator for example) can change the file. Try this: SECURITY_ATTRIBUTES m_pSecAttrib; SECURITY_DESCRIPTOR* m_pSecDesc; m_pSecDesc = (SECURITY_DESCRIPTOR*)LocalAlloc(LPTR, SECURITY_DESCRIPTOR_MIN_LENGTH); InitializeSecurityDescriptor(m_pSecDesc, SECURITY_DESCRIPTOR_REVISION); SetSecurityDescriptorDacl(m_pSecDesc,TRUE,(PACL)NULL,FALSE)) m_pSecAttrib.nLength = sizeof(SECURITY_ATTRIBUTES); m_pSecAttrib.bInheritHandle = TRUE; m_pSecAttrib.lpSecurityDescriptor = m_pSecDesc; It should create security descriptor with EVERYONE permission. Instead of NULL, send &m_pSecAttrib. Hope I helped.