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Go to Administrator → Home and click on the desired workflow timestamp. Go to Workflow Form Configuration tab to check the configuration of the Fallback, View By All Users ( used in the scheduling process), View Parameters Summary and Comments options. If they are set to ON, the options are visible in Portal for the selected workflow timestamp.
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Administrator → Home → Workflow Timestamp → Workflow Form Configuration tab:
Portal → Start Workflow form:
Windows Execution Group Configuration
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