OFN_SHAREAWARE top-level constant
Specifies that if a call to the OpenFile function fails because of a network sharing violation, the error is ignored and the dialog box returns the selected file name. If this flag is not set, the dialog box notifies your hook procedure when a network sharing violation occurs for the file name specified by the user. If you set the OFN_EXPLORER flag, the dialog box sends the CDN_SHAREVIOLATION message to the hook procedure. If you do not set OFN_EXPLORER, the dialog box sends the SHAREVISTRING registered message to the hook procedure.
const OFN_SHAREAWARE = 0x00004000;