What does the message "Error: Failed to save epoch." mean?

When attempting to save settings, the following error message may appear:

Rebooting the meter first is recommended, as this usually resolves the issue. The eGauge should also be on the latest firmware, so a firmware upgrade may be necessary.

This error message can appear when either of two conditions are met:

1. The date in the "Date & time when recording started" field under Settings -> General Settings is older than the database capacity of the eGauge. 

To correct this, set the "Date & time when recording started" field to a time more recent that the limit of the database capacity. To check your database capacity, append /cgi-bin/get?db to the end of the eGauge URL. For example: http://DEVNAME.egaug.es/cgi-bin/get?db (replace DEVNAME with the device name of the eGauge). Note that this may not work on older firmware. The same approach can be used with devices connecting to the newer version of the proxy, For example: http://DEVNAME.egauge.io/cgi-bin/get?db

2. The date in the "Date & Time" field under Settings -> Date & Time is set to a point in the future. 

To correct this, set the "Date & Time" to the current date and time as displayed on your computer. If the eGauge is connected to an NTP server this setting does not have to be precise; as long as the date and time is within a few minutes of the actual date and time the eGauge will automatically correct the offset.