I noticed this issue the other day, found this thread, then tried several of the suggestions here to fix it. Can't be sure what I did (either creating the dumby cache folder in root, or enabling the "Purge Cache" item in the schedule (was disabled) - but the error went away while still in 5.2.2.
The question I have may/may not be related. When I first notice this issue, there were (and still are) 5 "Purge Module Cache" items in the schedule. All enabled. All (seemingly) with the same exact settings. Of course I disabled 4 of them...danced around until I got that one item to proccess with success...then upgraded DNN5.2.2 to 5.3.1. The 4 (disabled) items are still in the cache (copied below). Where did they come from? Are they safe to delete?
Please take a look at the schedule below and advise...any recomendations are appreciated.
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Name Enabled Frequency Retry
Purge Users Online Enabled Every 1 Minute Every 5 Minutes
Purge Site Log Enabled Every 1 Day Every 2 Hours
Purge Schedule History Enabled Every 1 Day Every 2 Days
Purge Log Buffer Enabled Every 1 Minute Every 5 Minutes
Send Log Notifications Every 5 Minutes Every 10 Minutes
Search Engine Scheduler Enabled Every 24 Hours Every 24 Hours
Purge Cache Enabled Every 2 Hours Every 30 Minutes
Hyper.Modules.EventsCalendar..... Enabled Every 30 Minutes Every 10 Minutes
Adequation.DNN.XModIDEModule......... Enabled Every 1 Hour Every 1 Day
OnyakTech.Novus.Utilities.UpdateRSS......... Enabled Every 1 Day Every 20 Minutes
OnyakTech.HostCommander............... Every 1 Day Every 20 Minutes
Active.Modules.Forums.MC.MailConnector......... Enabled Every 5 Minutes Every 5 Minutes
Active.Modules.Forums.Queue.Scheduler........ Enabled Every 1 Minute Every 1 Minute
Purge Module Cache Enabled Every 1 Minute Every 30 Seconds
Purge Module Cache Every 1 Minute Every 30 Seconds
Purge Module Cache Every 1 Minute Every 30 Seconds
Purge Module Cache Every 1 Minute Every 30 Seconds
Purge Module Cache Every 1 Minute Every 30 Seconds
Messaging Dispatch Enabled Every 1 Minute Every 30 Seconds
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