Mvsckey Not Found Exclusive — _verified_

Use the system command D GRS,RES=(*,dataset.name) to see who currently owns the resource. This will tell you the Job Name and the type of lock (Shared vs. Exclusive). 2. Check Job Dependencies

Another user might be editing the dataset in ISPF. mvsckey not found exclusive

💡 when you only need to read the data. This prevents your job from blocking others. Use the system command D GRS,RES=(*,dataset

Look at your current JCL. If you are requesting DISP=OLD but another task only needs DISP=SHR , you may be creating your own bottleneck. 3. Verify VSAM Sharing Options Use the system command D GRS