I have multiple 2663-222 on/off outlets that control lights all around the house. For the last several months I have noticed that randomly several of the light will either not turn on or turn off at their scheduled times. Also have many 2477D switches on the schedules but these all appear to run correctly. I can control the 2663's on/off using the app, its just the schedules that do not run everyday. Some days it will be outlet 1 & 2 that don't turn on or off then the next day it will be outlet 3 & 4. It is very random.

Still using the 994i

I have restarted it several times, pulled the mem cards to make sure it is seated good. Unplugged the PLM to power cycle it which did not help.

Any help or guidance would be great.

Sounds like a communication issue at the time of schedule or a bad device. A single bad device in the scene can cause strange issues. If you can control from isy it is no the likely culprit.

@KYnewbie

Probably noise/interferrence on the powerline. Take a look at this troubleshooting article

INSTEON: Troubleshooting Communications Errors - Universal Devices, Inc. Wiki

Thanks for the ideas. I have moved the PLM to a different outlet as it was plugged into an outlet with the transformer for the alarm system (It has been that way for 10 years).

It could be due to a noisy transformer, after 10 years things can fail

Did moving the PLM resolve your problem?

Just moved it this morning. I will update here tomorrow morning after all the schedules run tonight.