I faced kind of issue before, check out below you can try the solution as mentioned.
Thanks Madhusudhan for your quick response. Tried this and it didn't work.
Have you tried to check to below logs
Essbase Not Starting Using OPMN, Receive Fatal Error: "Cannot open essbase.log file" (Doc ID 1574200.1)
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Try to clear (backup and delete) your state directory under opmn. See if you can run the "opmnctl startall" command then to see if it generates a new state folder for not. If not then there's likely an issue with your opmn.xml file. Start there and see what happens. I often find stepping through the config process over again helps (which you've likely done already) but sometimes a typo will pop up at me. You can also try checking your opmn.xml in IE our other XML checker to ensure no syntax errors. If it won't open in IE (blank) then there's likely a syntax issues and that would certainly cause open to fail and not log anything.
if you can, check your opmn.xml file and post it or snd it, feel free! Just the out anything personal/identifying first.
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