I oversea about 20 users and some have the issues and others do not.
Existing_GDB = arcpy.GetParameterAsText(2) # Path to working GDB
FP1 = os.path.abspath(Existing_GDB)
arcpy.management.AddJoin(in_layer, in_field, join_table, join_field, fieldlist)
arcpy.management.CopyFeatures(in_layer, fr"{FP1}\out_layer")
For the majority of users the Join will work and the fields and info will be copied to the out_layer which we'll then do further processing on. For a select few they get <null> values in all the fields that were joined from the join_table. Is there a work around?