You could try reinstalling AC. Before you uninstall it, you might want to move
client_cell_1.dat,
client_highres.dat, and
client_portal.dat from the AC folder (default:
C:\Program Files\Turbine\Asheron's Call - Throne of Destiny) to the Desktop so that you can restore them after you reinstall and avoid a long download.
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[LotRO] Digero (Guardian), Digrim (Burglar), Dignite (LM), Azrea (Hunter) - Landroval
[AC] Digero, Lyera, Draxxe - Leafcull (Retired)
[CoH] Devil's Zealot, Scinta, Izzard - Guardian (Retired)
Digero's AC Decal Plugins:
http://decal.acasylum.com