Possible bug report. I was getting "OOB" errors one one band - 6m. Everything else worked fine.
The error occurred with two different radios and with both direct connections and going through Ham Radio Deluxe.
The software would sometimes work when going to this band and then later display random numbers in the frequency window with an OOB error. Other times would immediately produce an OOB error.
If the radio was set to None, the frequency changed manually in the radio, and 6m selected from the band box the software would work and log correctly.
The cause appears to be an entry in the Station Information window under [Settings], [Frequencies]. There was a single entry for 6m. When this entry was removed the software started working with no problems on 6m.