Message type: E = Error
Message class:  IW - Order Processing 
Message number: 326
Message text: Equipment task list & & included
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The SAP error message IW326 typically indicates that there is an issue with the equipment task list in the context of maintenance planning or work order processing. The message usually states that the task list for the specified equipment is not available or is not properly configured.
Cause: Missing Task List: The equipment does not have an associated task list defined in the system. Incorrect Configuration: The task list may not be correctly configured or may not be assigned to the equipment. Authorization Issues: The user may not have the necessary authorizations to access the task list. Data Inconsistencies: There may be inconsistencies in the master data related to the equipment or task list.
Solution: Check Task List Assignment: Navigate to the equipment master record (transaction code IE03). Verify if the task list is assigned to the equipment. If not, you may need to create or assign a task list. Create/Modify Task List: If the task list does not exist, you
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