Hi I made the update from 4.7.0.0 to 4.9.0.0 and have the same problem again. Few weeks ago I tried a other communication way with OWFS. Here I wanted to read the value from file /mnt/1wire/temperatur At least I found the problem that codesys blocks reading from files. I added the two lines in /etc/CODESYSControl.cfg ;raspberry [SysFile] ForceFilePath=0 ForceIecFilePath=0 Now it works again. Regard August