varchar convert to date at universe platform error (SQL database)

Hello Everybody .

Database SQL Server 2008

BI 4.1 SP4 P1

I want to change an area format which. is ddmmyyy (varchar) . I want to change varchar area to date format area at universe.

My formula :

CASE WHEN

LEN (VIKODWH.dbo.DWH_FACT_SIPARIS_MASTER.genel_veri10) < '8' OR LEN(VIKODWH.dbo.DWH_FACT_SIPARIS_MASTER.genel_veri10) is NULL THEN VIKODWH.dbo.DWH_FACT_SIPARIS_DETAY.teslim_tarih ELSE

Convert(varchar,convert(varchar(10),VIKODWH.dbo.DWH_FACT_SIPARIS_MASTER.genel_veri10,101),101) end

Parse is Ok but I want to display it give me errors .

ettiğimizde “Exception: DBD, [Microsoft SQL Server Native Client 11.0] : Conversion failed when converting date and/or time from character string.State: 22007”

What can I do ? Could you help me please ?