In Knime 2.11.2, if I try to write to a network drive (in this case a Synology DS415+ NAS) with a CSV writer node I get an error (no write permissions in directory). In previous versions of Knime (2.10.x and 2.9.x) this works without an issue and I am able to write the CSV to the network drive without a problem. I have tried this with 3 different machines all of which have this issue of not being able to write to a network drive on 2.11.2, so it seems to be a bug.
I tried using the direct path too, ie \\servername\directory. This still gives the same error. Even with the direct path, the note stays red, with the warning symbol, saying \\servername\directory isn't writable and cannot be executed.
WARN CSV Writer Directory '\\DiskStation\clients\' is not writable
Is the exact message, but even though it is a warning the node will not execute. The message in the node says "Error: no write permissions in directory" but only if it is a network drive. If you use the full path, it only throws the warning.
2015-03-04 14:20:02,788 DEBUG main WorkflowManager : Added new connection from node 3:1(1) to node 3:2(1)
2015-03-04 14:20:02,788 DEBUG KNIME-Workflow-Notifier WorkflowEditor : Workflow event triggered: WorkflowEvent [type=CONNECTION_ADDED;node=null;old=null;new=STD[3:1(1) -> 3:2( 1)];timestamp=04-Mar-2015 14:20:02]
2015-03-04 14:20:02,788 DEBUG KNIME-Workflow-Notifier WorkflowRootEditPart : WorkflowRoot: workflow changed, refreshing children/connections..
2015-03-04 14:20:02,791 DEBUG main ConnectionContainerEditPart : refreshing visuals for: STD[3:1(1) -> 3:2( 1)]
2015-03-04 14:20:02,791 DEBUG main ConnectionContainerEditPart : modelling info: null
2015-03-04 14:20:02,791 DEBUG main ConnectionContainerEditPart : refreshing visuals for: STD[3:1(1) -> 3:2( 1)]
2015-03-04 14:20:02,792 DEBUG main ConnectionContainerEditPart : modelling info: null
2015-03-04 14:20:04,736 DEBUG main NodeContainerEditPart : File Reader 3:1 (EXECUTED)
2015-03-04 14:20:04,737 DEBUG main NodeContainerEditPart : CSV Writer 3:2 (IDLE)
2015-03-04 14:20:53,478 WARN main CSV Writer : Directory '\\DiskStation\clients\' is not writable
2015-03-04 14:20:55,317 WARN main CSV Writer : Directory '\\DiskStation\clients\' is not writable
I believe that is the correct part of the log, but let me know if it is not.
I see, I guess the destination file does not exist yet. I agree this is annoying but unfortunately I don't have an immediate solution yet. We added these checks to have better error and warning messages but were not aware that Java has a serious bug when checking the permissions on network drives under Windows. All other locations work as expected.
A work around is to use the \\servername\path\filename.csv as the url, create an empty file in the destination with the name, and then append to it, which works fine. It still doesn't work as a drive letter.