I recently upgraded one of my test sites from DNN 6.2 to DNN 7.4.0.  After that I started seeing scheduler failures:

EXCEPTION:Access to the path '\\<server path>\Portals\<portalid>-System\Cache\Pages\' is denied

Message:Access to the path '\\<server path>\Portals\<portalid>-System\Cache\Pages\' is denied.

StackTrace:

   at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
   at System.IO.Directory.InternalCreateDirectory(String fullPath, String path, Object dirSecurityObj, Boolean checkHost)
   at System.IO.Directory.InternalCreateDirectoryHelper(String path, Boolean checkHost)
   at System.IO.Directory.CreateDirectory(String path)
   at DotNetNuke.Services.ModuleCache.FileProvider.GetCacheFolder(Int32 portalId)
   at DotNetNuke.Services.ModuleCache.FileProvider.PurgeExpiredItems(Int32 portalId)
   at DotNetNuke.Services.ModuleCache.PurgeModuleCache.DoWork()

In looking @ the source, it seems that there is now a new property portalInfo.HomeSystemDirectoryMapPath (see FileProvider.cs line 96).  It looks like the intent is to get the cache files out of the portal's 'public' directory and into a place that only the  CMS can see, makes sense to me.  

In my case, the issue was that the webhead did not have write permissions into the Portals directory.  Once I corrected that, things got quite a bit better.

My question: Is there an easy way to cleanup all the old cache directories?  (the ones in the Portals\<portalid>\Cache directory)  I'm running on a shared host with only FTP access to the file system.

Thanks!