This is a known problem, that seems to happen on some – slower – machines.
When double-clicking a file in Windows Explorer the registered executable for this file format is identified. Then there are three possibilities:
- The found executable is already running and supports DDE communication: In this case Windows Explorer sends an open-command via DDE to the application.
- The found executable is not running but supports DDE communication: Windows Explorer starts the executable, waits until it thinks the program should be running and then sends the open-command via DDE.
- The found executable does not support DDE communication: In this case the program is started and the database that should be open is given as a command line agument.
Under the conditions given above the system will end up in case 2. Starting up FlexPro can take a while and while this is happening it can not react on DDE commands. When Windows Explorer sends the DDE command it will get no answer, assumes an error and issues the error message given above. This message can be ignored, but there is also a ways to get rid of it:
- Start Windows Explorer
- Execute the ‘Folder options’ command in the ‘Tools’ menu.
- Switch to the ‘File types’ property page.
- Select the entry for the FPD extension in the shown file type list.
- Click the ‘Advanced’ button and the ‘Edit File Type’ dialog box is displayed.
- Select the ‘open’-command from the list and edit it by clicking at ‘Edit’.
- Remove the check from the ‘Use DDE’
When disabling DDE you should consider that only one instance of FlexPro can be run at a time. This means if FlexPro is already open and you double-click a database in Explorer nothing will happen.