I get error 1000 in Engine Log when changing screen resolution

I get error 1000 when changing screen resolution
as reported in engine log.
1: What does this mean?
2: Happens "randomly" i.e. sometimes change in resolution works and othertimes not.

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2024-05-10 12:07:14 Action 15792030 failed: Set Screen Resolution failed to set resolution because setting display mode failed with error 1000


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      2024-05-10 12:11:17 Action 15792030 failed: Set Screen Resolution failed to set resolution because setting display mode failed with error 1000


       2024-05-10 12:11:17 Set Screen Resolution failed to set resolution because setting display mode failed with error 1000. Macro “02) [SetScreenRes.]1.   Internal  1440 x 900 My default” cancelled (while executing Set Screen “SCREENINDEX(Internal)” to Resolution “1440,900”).

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2024-05-10 12:02:21 Execute macro “Switch to KM Editor              CC+K   ” from trigger The Hot Key ⌃⌘K is pressed
2024-05-10 12:05:44 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:06:03 Execute macro “71) [SetScreenRes.]S   Show variable values , including Instance variables.  ” from trigger Duplicate Macro Palette
2024-05-10 12:06:04 Log: >>>  
Last message repeated 2 times
2024-05-10 12:06:36 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:06:52 Execute macro “22) [SetScreenRes.]6.  TOSH2.  1600x900. Good second screen” from trigger Duplicate Macro Palette
2024-05-10 12:07:11 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:07:14 Execute macro “02) [SetScreenRes.]1.   Internal  1440 x 900 My default” from trigger Duplicate Macro Palette
2024-05-10 12:07:14 Action 15792030 failed: Set Screen Resolution failed to set resolution because setting display mode failed with error 1000
2024-05-10 12:07:14 Set Screen Resolution failed to set resolution because setting display mode failed with error 1000. Macro “02) [SetScreenRes.]1.   Internal  1440 x 900 My default” cancelled (while executing Set Screen “SCREENINDEX(Internal)” to Resolution “1440,900”).
2024-05-10 12:07:28 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:07:35 Execute macro “02) [SetScreenRes.]1.   Internal  1440 x 900 My default” from trigger Duplicate Macro Palette
2024-05-10 12:07:35 Action 15792030 failed: Set Screen Resolution failed to set resolution because setting display mode failed with error 1000
2024-05-10 12:07:35 Set Screen Resolution failed to set resolution because setting display mode failed with error 1000. Macro “02) [SetScreenRes.]1.   Internal  1440 x 900 My default” cancelled (while executing Set Screen “SCREENINDEX(Internal)” to Resolution “1440,900”).
2024-05-10 12:07:44 Execute macro “Switch to Preferences  - Displays  COC+D” from trigger The Hot Key ⌃⌥⌘D is pressed
2024-05-10 12:08:18 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:08:57 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:09:14 Execute macro “91) [SetScreenRes.]O  Debug. Open KM Engine Log. SCO+E” from trigger Duplicate Macro Palette
2024-05-10 12:10:36 Execute macro “Switch to Preferences  - Displays  COC+D” from trigger The Hot Key ⌃⌥⌘D is pressed
2024-05-10 12:11:11 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:11:17 Execute macro “02) [SetScreenRes.]1.   Internal  1440 x 900 My default” from trigger Duplicate Macro Palette
2024-05-10 12:11:17 Action 15792030 failed: Set Screen Resolution failed to set resolution because setting display mode failed with error 1000
2024-05-10 12:11:17 Set Screen Resolution failed to set resolution because setting display mode failed with error 1000. Macro “02) [SetScreenRes.]1.   Internal  1440 x 900 My default” cancelled (while executing Set Screen “SCREENINDEX(Internal)” to Resolution “1440,900”).
2024-05-10 12:12:14 Execute macro “92) [SetScreenRes.]L   Debug.  KM Engine Add Log  Entry [SCO+L ]” from trigger Editor
2024-05-10 12:12:39 Log: >>> works ok using sys pref display
2024-05-10 12:12:55 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:13:03 Execute macro “04) [SetScreenRes.]2.  Internal. 1536 x 960 My small text” from trigger Duplicate Macro Palette
2024-05-10 12:13:36 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:13:39 Execute macro “02) [SetScreenRes.]1.   Internal  1440 x 900 My default” from trigger Duplicate Macro Palette
2024-05-10 12:14:23 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:14:52 Execute macro “92) [SetScreenRes.]L   Debug.  KM Engine Add Log  Entry [SCO+L ]” from trigger Duplicate Macro Palette
2024-05-10 12:15:00 Execute macro “[CRON] ⏰ Periodic Every xx minutes  switch/ activate Diary/Calendar” from trigger Every 15 minutes between 6:30-23:59 every day
2024-05-10 12:15:11 Log: >>> turn off all resolutions
2024-05-10 12:16:13 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:16:15 Execute macro “02) [SetScreenRes.]1.   Internal  1440 x 900 My default” from trigger Duplicate Macro Palette
2024-05-10 12:16:36 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:16:43 Execute macro “04) [SetScreenRes.]2.  Internal. 1536 x 960 My small text” from trigger Duplicate Macro Palette
2024-05-10 12:17:00 Execute macro “00) [SetScreenRes.]     Macro Palette from status bar or SCO+§ ” from trigger The Hot Key ⌃⌥⇧Section Sign is pressed
2024-05-10 12:17:28 Execute macro “01) [SetScreenRes.]0.   README & VERSION LOG”