Batch execution fails while workflow runs fine in GUI

Hi everyone,

I have developed a workflow and would like to execute it using a batch script. Unfortunately, an error occurs during execution and I suspect that some of the nodes may not be suitable for batch processing. Could you please provide your assessment on this?

In the classic UI, I defined the variable “var_batch_directory_value” and then used “String to Path (Variable)” to generate a path variable with the suffix “_location” (i.e., var_batch_directory_value_location). I then use this variable in “List Files/Folders” to read CSV files.

In the GUI, the workflow runs without any issues.

When using the batch script, an error unfortunately occurs:

LOG-file
2026-02-26 10:23:39,573 : WARN  : KNIME-Worker-2-Collect Local Metadata 3:1 :  : Node : List Files/Folders : 3:11 : Errors loading flow variables into node : Errors overwriting node settings with flow variables: Unknown variable "var_batch_directory_value_location"
2026-02-26 10:23:39,577 : INFO  : main :  : BatchExecutorImpl :  :  : Workflow execution done Finished in 10 secs (10609ms)
2026-02-26 10:23:39,609 : INFO  : main :  : BatchExecutorImpl :  :  : ========= Workflow did not execute sucessfully ============
2026-02-26 10:23:43,316 : INFO  : KNIME shutdown hooks - org.knime.core.util.FileUtil$$Lambda/0x0000022e5e4b2a08 :  : FileUtil :  :  : Deleting 2 temporary files.
2026-02-26 10:33:43,188 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : #########################################################################################
2026-02-26 10:33:43,192 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : #                                                                                       #
2026-02-26 10:33:43,192 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # Welcome to KNIME Analytics Platform v5.10.0.v202601281134 (Build January 28, 2026)    #
2026-02-26 10:33:43,193 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # Based on Eclipse, http://www.eclipse.org                                              #
2026-02-26 10:33:43,193 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : #                                                                                       #
2026-02-26 10:33:43,193 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : #########################################################################################
2026-02-26 10:33:43,193 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : #                                                                                       #
2026-02-26 10:33:43,193 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # Copyright by KNIME AG, Zurich, Switzerland and others.                                #
2026-02-26 10:33:43,193 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # Website: http://www.knime.com                                                         #
2026-02-26 10:33:43,193 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # E-mail: contact@knime.com                                                             #
2026-02-26 10:33:43,193 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : #                                                                                       #
2026-02-26 10:33:43,194 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : #########################################################################################
2026-02-26 10:33:43,194 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # For more details see the KNIME log file:                                              #
2026-02-26 10:33:43,194 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # C:\pa-temp\KNIME\F101\workspace\.metadata\knime\knime.log
2026-02-26 10:33:43,194 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : #---------------------------------------------------------------------------------------#
2026-02-26 10:33:43,228 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # logging date=Do. Feb 26 10:33:43 MEZ 2026
2026-02-26 10:33:43,229 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # java.version=21.0.9
2026-02-26 10:33:43,229 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # java.vm.version=21.0.9+10-LTS
2026-02-26 10:33:43,229 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # java.vendor=Eclipse Adoptium
2026-02-26 10:33:43,229 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # os.name=Windows Server 2022
2026-02-26 10:33:43,230 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # os.arch=amd64
2026-02-26 10:33:43,230 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # number of CPUs=8
2026-02-26 10:33:43,230 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # assertions=off
2026-02-26 10:33:43,246 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # host=srv29
2026-02-26 10:33:43,250 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # username=paadmin
2026-02-26 10:33:43,250 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # max mem=8192MB
2026-02-26 10:33:43,253 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # application=org.knime.product.KNIME_APPLICATION
2026-02-26 10:33:43,262 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : # KNID=11-c5cd0c816325fc0c-01-096ac765332a6e29
2026-02-26 10:33:43,262 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : NodeLogger :  :  : #########################################################################################
2026-02-26 10:33:42,968 : INFO  : Start Level: Equinox Container: 59ad776e-5ac8-4820-b9d0-01f2aa5f3b13 :  : RegisterBouncyCastleProvider :  :  : Added BouncyCastleProvider to Java Security providers
2026-02-26 10:33:44,751 : INFO  : main :  : StringHistory :  :  : History file 'C:\pa-temp\KNIME\F101\workspace\.metadata\knime\history_database_drivers.txt' does not exist.
2026-02-26 10:33:44,752 : INFO  : main :  : StringHistory :  :  : History file 'C:\pa-temp\KNIME\F101\workspace\.metadata\knime\history_database_urls.txt' does not exist.
2026-02-26 10:33:44,791 : INFO  : main :  : BatchExecutorImpl :  :  : ===== Executing workflow \\srv28\KNIME\F101\KNIME-Workflow\F101 =====
2026-02-26 10:33:45,131 : INFO  : main :  : ProcessWatchdog :  :  : KNIME Process Watchdog memory limit not configured
2026-02-26 10:33:45,131 : INFO  : main :  : ProcessWatchdog :  :  : External process memory watchdog is disabled, because the memory limit is set to -1
2026-02-26 10:33:45,133 : INFO  : main :  : InitWindowlessCEF :  :  : Initializing windowless CEF instance
2026-02-26 10:33:45,577 : INFO  : Thread-13 :  : InitWindowlessCEF :  :  : CEF instance initialized in 443ms
2026-02-26 10:33:53,209 : WARN  : main :  : Node : Create Folder : 3:1:0:71 : Errors loading flow variables into node : Errors overwriting node settings with flow variables: Unknown variable "data-path"
2026-02-26 10:33:53,225 : WARN  : main :  : Node : Create Folder : 3:1:0:71 : Errors loading flow variables into node : Errors overwriting node settings with flow variables: Unknown variable "data-path"
2026-02-26 10:33:53,563 : WARN  : main :  : Node : Create Folder : 3:1:0:71 : Errors loading flow variables into node : Errors overwriting node settings with flow variables: Unknown variable "data-path"
2026-02-26 10:33:53,640 : WARN  : main :  : Node : List Files/Folders : 3:11 : Errors loading flow variables into node : Errors overwriting node settings with flow variables: Unknown variable "var_batch_directory_value_location"
2026-02-26 10:33:54,558 : WARN  : main :  : Node : Create Folder : 3:1:0:71 : Errors loading flow variables into node : Errors overwriting node settings with flow variables: Unknown variable "data-path"
2026-02-26 10:33:54,780 : WARN  : main :  : Node : Create Folder : 3:1:0:71 : Errors loading flow variables into node : Errors overwriting node settings with flow variables: Unknown variable "data-path"
2026-02-26 10:33:55,059 : INFO  : KNIME-Worker-0-Single Selection Widget 3:326 :  : LocalNodeExecutionJob : Single Selection Widget : 3:326 : Single Selection Widget 3:326 End execute (0 secs)
2026-02-26 10:33:55,059 : INFO  : KNIME-Worker-4-Extract Context Properties 3:1:0:2 :  : LocalNodeExecutionJob : Extract Context Properties : 3:1:0:2 : Extract Context Properties 3:1:0:2 End execute (0 secs)
2026-02-26 10:33:55,059 : INFO  : KNIME-Worker-5-Component Input 3:1:0:72 :  : LocalNodeExecutionJob : Component Input : 3:1:0:72 : Component Input 3:1:0:72 End execute (0 secs)
2026-02-26 10:33:55,059 : INFO  : KNIME-Worker-1-Date&Time Configuration 3:321 :  : LocalNodeExecutionJob : Date&Time Configuration : 3:321 : Date&Time Configuration 3:321 End execute (0 secs)
2026-02-26 10:33:55,231 : INFO  : KNIME-Worker-3-Table Creator 3:339 :  : LocalNodeExecutionJob : Table Creator : 3:339 : Table Creator 3:339 End execute (0 secs)
2026-02-26 10:33:55,231 : INFO  : KNIME-Worker-0-Variable to Table Row 3:1:0:4 :  : LocalNodeExecutionJob : Variable to Table Row : 3:1:0:4 : Variable to Table Row 3:1:0:4 End execute (0 secs)
2026-02-26 10:33:55,600 : INFO  : KNIME-Worker-5-Column Expressions (legacy) 3:1:0:3 :  : LocalNodeExecutionJob : Column Expressions (legacy) : 3:1:0:3 : Column Expressions (legacy) 3:1:0:3 End execute (0 secs)
2026-02-26 10:33:55,792 : INFO  : KNIME-Worker-1-Column Expressions (legacy) 3:1:0:5 :  : LocalNodeExecutionJob : Column Expressions (legacy) : 3:1:0:5 : Column Expressions (legacy) 3:1:0:5 End execute (0 secs)
2026-02-26 10:33:55,809 : INFO  : KNIME-Worker-4-Java Snippet (simple) 3:1:0:7 :  : LocalNodeExecutionJob : Java Snippet (simple) : 3:1:0:7 : Java Snippet (simple) 3:1:0:7 End execute (0 secs)
2026-02-26 10:33:55,967 : INFO  : KNIME-Worker-3-String to Path 3:1:0:8 :  : LocalNodeExecutionJob : String to Path : 3:1:0:8 : String to Path 3:1:0:8 End execute (0 secs)
2026-02-26 10:33:55,985 : INFO  : KNIME-Worker-0-Table Row to Variable 3:1:0:9 :  : LocalNodeExecutionJob : Table Row to Variable : 3:1:0:9 : Table Row to Variable 3:1:0:9 End execute (0 secs)
2026-02-26 10:33:56,019 : INFO  : KNIME-Worker-5-Create Folder 3:1:0:71 :  : LocalNodeExecutionJob : Create Folder : 3:1:0:71 : Create Folder 3:1:0:71 End execute (0 secs)
2026-02-26 10:33:56,031 : ERROR : KNIME-Worker-1-String to Path (Variable) 3:1:0:74 :  : Node : String to Path (Variable) : 3:1:0:74 : Execute failed: Some of the selected variables contain empty strings.
java.lang.IllegalArgumentException: Some of the selected variables contain empty strings.
                at org.knime.core.node.util.CheckUtils.checkArgument(CheckUtils.java:260)
                at org.knime.core.node.util.CheckUtils.checkArgument(CheckUtils.java:121)
                at org.knime.filehandling.utility.nodes.stringtopath.variable.StringToPathVariableNodeModel.execute(StringToPathVariableNodeModel.java:197)
                at org.knime.core.node.NodeModel.executeModel(NodeModel.java:605)
                at org.knime.core.node.Node.invokeFullyNodeModelExecute(Node.java:1331)
                at org.knime.core.node.Node.execute(Node.java:1038)
                at org.knime.core.node.workflow.NativeNodeContainer.performExecuteNode(NativeNodeContainer.java:618)
                at org.knime.core.node.exec.LocalNodeExecutionJob.mainExecute(LocalNodeExecutionJob.java:98)
                at org.knime.core.node.workflow.NodeExecutionJob.internalRun(NodeExecutionJob.java:201)
                at org.knime.core.node.workflow.NodeExecutionJob.run(NodeExecutionJob.java:120)
                at org.knime.core.util.ThreadUtils$RunnableWithContextImpl.runWithContext(ThreadUtils.java:369)
                at org.knime.core.util.ThreadUtils$RunnableWithContext.run(ThreadUtils.java:223)
                at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
                at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
                at org.knime.core.util.ThreadPool$MyFuture.run(ThreadPool.java:143)
                at org.knime.core.util.ThreadPool$Worker.run(ThreadPool.java:277)
2026-02-26 10:33:56,344 : WARN  : KNIME-Worker-2-Collect Local Metadata 3:1 :  : Node : List Files/Folders : 3:11 : Errors loading flow variables into node : Errors overwriting node settings with flow variables: Unknown variable "var_batch_directory_value_location"
2026-02-26 10:33:56,347 : INFO  : main :  : BatchExecutorImpl :  :  : Workflow execution done Finished in 11 secs (11555ms)
2026-02-26 10:33:56,389 : INFO  : main :  : BatchExecutorImpl :  :  : ========= Workflow did not execute sucessfully ============
2026-02-26 10:35:23,568 : INFO  : KNIME shutdown hooks - org.knime.core.util.FileUtil$$Lambda/0x000002c13e4b5898 :  : FileUtil :  :  : Deleting 2 temporary files.

Thanks in advance!

try using the variable creator node, instead of configuration or widget nodes.
secondly, did you try running batch “standalone” or was Knime open while you tried executing? Some versions ago they implemented a “fix” which prevents running multiple batch sessions or batch sessions that access the same (default) workspace in the background.

@Kopp you might have to set this as a workflow variable in KNIME not just a variable to be created inside the workflow or in a dynamic way. It seems KNIME Batch does not ‘like’ any relative path operations inside a batch process.


Blog: “KNIME Batch Processing on Windows and MacOS

1 Like