Some more error detail:

[UnauthorizedAccessException: Access to the path '\httpdocs\umbraco\theoutfield\exportmedia\handlers' is denied.]
   System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath) +216
   System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost) +1430
   System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, String msgPath, Boolean bFromProxy) +208
   System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share) +87
   System.IO.File.Open(String path, FileMode mode) +72
   TheOutfield.UmbExt.ExportMedia.Handlers.ExportMedia.ParseMedia(HttpContext context, Media media, ZipFile zip, String path) +1485
   TheOutfield.UmbExt.ExportMedia.Handlers.ExportMedia.ProcessRequest(HttpContext context) +606
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +913
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +165

Figured this as a permissions problem on my install - but unfortunately, after being solved, that led to a:

The process cannot access the file 'filepath/pb050017.jpg' because it is being used by another process.

I will post an update if i solve it this - it seems to be a pretty common error. :)

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