You cannot summon that retainer right now.
I noticed two other threads regarding the same issue, but I figured since this was still happening after the hotfix, it was worth posting.
ISP:
WOW! Internet
Type of Internet Connection:
Cable
Internet Connection Speed:
16 Mbits down / 1 Mbits up
Date & Time:
May 15th, 2012, 10:50 PM EST.
Frequency:
Always
Character Name:
Meta Tron
Race:
Elezen F
World:
Durandal
Class/Level:
Archer/Bard 48
Area and Coordinates:
At any retainer summoning bell. Example: X: 6 Y: 4
Party or Solo:
Solo, but has occurred in a full party (8) as well.
NPC Name:
None (unless you count "???")
Monster Name:
None
In-Game Time:
21:45
Steps:
-Proceed to any Summoning Bell. Have tried Limsa Lominsa and Ul'dah summoning bells near the Levequest NPCs. Have also tried summoning bells in all three mercantile houses.
-Click on Summoning Bell. Popup menu opens to confirm retainer (important note: retainer is currently assigned to Limsa Lominsa - Southern Islands. She is not in a Market Ward)
-Click on retainer named "Metalgears". The following popup message appears:
"Summoning a retainer with an open bazaar will close that bazaar and end any remaining stand lease. Summon this retainer?"
-Click "Yes"
-Wait for retainer. Bell rings for about 3-4 seconds
-Retainer does not appear. Following message is displayed: "You cannot summon that retainer right now."
Additional details: The issue first started around 12:00 PM EST on 5/13/2012. I was trying to summon the retainer, and I disconnected during the process (FFXIV also crashed). Since then, I have been unable to summon the retainer.
Thank you for your support, and I will check back to see if you need any more information.