>Thanks, but it is mostly about the fact that I cannot remove the statistic. Basically, I do not want to remove the statistics that refers to existing indexes. But, on some tables, some statistics are created as _WA and that shows me that I need to create an index. Once the index is created, the statistics under the index name is created and maintained. So, by then, I can then go in Statistics and remove the old _WA reference. This is what I cannot do. On my PC and on the server, I have full priviledges. I wonder what causes the Delete to be disabled.

The only way I have found to remove those statistics is with the DROP command:

DROP STATISTICS [Table]._WA_Sys_00000007_7EF6D905