There is no reason for the cursor. Try a joined UPDATE to get less code and much better performance:

UPDATE t SET

t.Code = md.Code,

t.GPOName = md.GPONam,

t.TotalMO = md.TotalMO

FROM tempDailyUPD

JOIN

(

select

distinct(masterdata.gpo_id) as Code,

gpo.name as GPOName,

count(masterdata.mno) as TotalMO

from masterdata, gpo

where masterdata.gpo_id = gpo.gpo_id

group by masterdata.gpo_id, gpo.name

) md

ON t.[Your Destination JOIN Column] = md..[Your Source JOIN Column]

Notice the ON part of the JOIN. Here you have to define the relation between both tables which seems to be missing in your script.

Flo