The Thermal Monitoring System which, e.g., provides the telescope structure temperature to the TCS needed to keep the telescope focused, is still running on an old MSDOS computer. The idea was to port it to a Linux computer when the new TCS would start operating, but the network interface failed which makes the shift obligatory.
One big advantage of porting the system is that the temperature data will be stored in a database which allows for a much more refined analysis.