workflow cannot be opened


I'm using Knime 2.4 and it failed to open an older workflow with the following message:

> WARN      VMFileLocker     I/O Error while trying to lock dir "/Volumes/tds/projects/knime/2011_screen-analysis/2011-02-14_ScreenAnalysis": Lock could not be aquired on: '/Volumes/tds/projects/knime/2011_screen-analysis/2011-02-14_ScreenAnalysis/.knimeLock'. Reason: Operation not supported

Any idea what is wrong??? I also added today the flag


to the Knime properties ini-file (MacOS and workspaces on network drives causes problems from time to time without the flag). But even removing this flag again, doen not help...

Edit: The workspace containing the workflow is located on a samba file system server.



no comments on this problem? We've seen it with other workflows too (and there was no modification at the config-file, so it has nothing to do with it).

I always seems to happen with workflows at our fileserver.

If it's a bug in KNIME 2.4 please let me know. I'd like to give an advice to our people how to proceed. (For example, they can build a new workspace locally and import their workflows to continue working).



Thanks, Antje, for reporting this and your help locating the problem.

The issue is resolved in v2.4.2.


I'm experiencing the same problem with Knime 2.4.2 under Win7 64-bits. My Knime project folder is on a synced file server. I can't create any new projects and cannot open old ones either without getting the VMFileLocker error.

Please advice!


I recently upgraded to Knime 2.7 and am having this exact problem described above. I'm using Mac OSX 10.6.8. Is there a potential bug fix for this?



Hi Eric, 

I haven't run into this problem yet, but I did do some reading up on other people experiencing similar problems.  It seems the likely culprit is the network file system, which is locking the file to prevent concurrent modification of the files in your workflow.  This could be exasperated by having multiple users trying to access the workflow simultaneously, or having KNIME quit "ungracefully" which could leave a lock hanging.  Do you have either of these types of problems?