I have been working on setting up my own template and have found some library parts that I cannot retrieve. Would anyone know a workaround on how to remove the missing library parts from the template so that those warning signs won't show up anymore? Thank you
Based on your error report, I think your can either upload those objects from AC 11 or respected library or find those balck spots out manually by turning on all the layers and use find and select with object for element type and library part name to locate them.
For Attributes you can manage them in Attributes manager.
26 errors are not many so, i think you can pin point them easily.