Does anyone know if this is a known bug? This is the TOP end crafted gear available. It not working seems very very very bad..

A big slap in the face to all high end crafters and those willing to grind the gps and mats to get the BEST gear if its sitting broken for this long...

Yep, it's broken and it's well known.

Given that this problem has been known for a while, I see little chance that they will bother to fix this because they're planning a major update on the set bonuses next month.

Item Sets
Item sets that increase healing as part of their two-, three-, or four-piece bonus now correctly display a percentage sign beside the amount of the increase.
Item sets that affect group members now state their maximum number of targets.
Set bonuses that affect group members no longer have their effect permanently ended when a group member leaves the wearer’s zone.
Fixed several issues that prevented item sets from applying their bonuses.
Several typographical errors in item set tooltips have been corrected.
Item sets now create visual effects when their bonuses trigger.
Many item set bonuses have become more powerful.
All item sets offer their most powerful bonus after the entire set has been collected, requiring either 3 or 5 pieces.
All item sets of 3 pieces give a minor bonus after collecting 2 out of 3 pieces.
All item sets of 5 pieces give a minor bonus after collecting 2, 3, and 4 pieces out of the total 5.
Berserking Warrior: This set’s bonus now works properly with Two-handed weapon abilities.
Buffer of the Swift: Fixed an issue that caused this set’s 5 piece bonus to have only a 10% chance to absorb damage.
Darkstride: This set’s 5 piece bonus no longer grants a smaller amount of stamina recovery than intended.
Defending Warrior: This item set’s damage type has been changed to Magic.
Dreugh King Slayer: This set’s 5 piece bonus no longer grants a smaller amount of stamina recovery than intended.
Ebon Armory: The item tooltip describes this set’s bonuses more clearly.
Healing Mage: This set’s bonus now affects a maximum of six targets, and its tooltip now specifies that it affects weapon damage.
Ice Furnace: The Ice Furnace item set now has a percentage chance to trigger instead of always firing.
Kyne’s Flight: Periodic damage from Acid Spray can now trigger this set’s 5 piece bonus.
Lord’s Mail: This set’s 5 piece bonus now triggers a cooldown when it activates.
Night’s Silence: Fixed an issue that prevented this set’s bonus from applying, and edited the tooltip to reflect the correct stealth bonus percentage at 60%.
Poisonous Serpent: This set’s tooltip now explains that the bonus only applies to light and heavy weapon attacks.
Sanctuary: This set’s 5 piece bonus now correctly applies to allies. We also fixed an issue that lowered its healing bonus.
Sergeant’s Mail: The item tooltip describes this set’s bonuses more clearly. Its 5 piece bonus can no longer occur twice in a row.
Shalidor’s Curse: This set’s 5 piece bonus now triggers correctly.
Shroud of the Lich: Bracers and shoulders in this set now have a sell value.
Thunderous Plate: This set’s 5 piece bonus now only triggers on melee attacks, as stated in its tooltip.
Twin Sisters: This set’s 5 piece bonus now lists its effect’s duration.
Wise Mage: This set’s tooltip describes this set’s effects more clearly.

Alot of changes to look forward to. Maybe jump on pts and take a look

hahahaahhahahaah. I'm sorry but it is insanely funny that OP is throwing such a fit and demands a zenimax person post in this thread and give him his 50k gold back!#$!$%%@%^@$@^% over a well known issue, he jes dint serrch vury guds. oh gnoes.

Quick! someone stop him before he hits social media! Call a media blackout! lulz!