Windows write filter
Since the persistent data are stored on a storage medium, the file and the path must be writeable. If you use the Windows write filter, the Windows partition is protected against write access operations, and the persistent data are not saved.
- Switch off the EWF, if you want to save persistent data.
- The FBWF and UWF do not have to be switched off, because an exception can be defined for the directory \Boot.
For Windows CE and Windows Embedded Compact 7 no Windows write filters are used.
FBWF exception list
By default an exception list is automatically created when the FBWF is switched on. The \Boot directory is already entered in this list. Check the configuration of the FBWF if you have made changes to the exception list.
The persistent data are saved by default under \TwinCAT\Boot in TwinCAT 2 and under \TwinCAT\3.1\Boot in TwinCAT 3.
The FBWF can be configured via the Beckhoff FBWF manager.