The error message may appear when reading message is obscure. It appears when trying to read an attribute from a faulty Pool device.
The basic problem is that the connection between the Pool device and the Tango device is
is somehow broken.
Reasons that have been observed so far:
- the online.xml entry describing the Pool device has a typo on in the device name or the typo
happened when the device was created using jive.
- The Tango server was not running while SardanaAIO.py was executed.
Btw.: if the Tango server has been stopped after SardanaAIO.py has bee executed,
an access to the corresponding Pool device will throw the meaningful error:
'Device <devName> is not exported'