The message is because the Box-Office is not yet connected to the device driver manager:
This could be because the device driver manager is not started (issue with the firefox package?), or there’s a certificate issue (good version of the pack?) or an anti-virus that is too strict and blocks the communication.
Has there been any changes of the configuration of these PC in the last days ?
Or the operator
The icon (printer with blue dots) should move to printer without blue dots (and no red cross) after less than one minute.