I have been playing around with a quite complex SQL Statement for a few days, and have gotten most of it working correctly.

I am having trouble with one last part, and was wondering if anyone could shed some light on the issue, as I have no idea why it isnt working:

INSERT INTO ExistingClientsAccounts_IMPORT
SELECT DISTINCT 
cca.AccountID, cca.SKBranch, cca.SKAccount, cca.SKName, cca.SKBase, 
cca.SyncStatus, cca.SKCCY, cca.ClientType, cca.GFCID, cca.GFPID, cca.SyncInput, 
cca.SyncUpdate, cca.LastUpdatedBy, cca.Deleted, cca.Branch_Account, cca.AccountTypeID
FROM         ClientsAccounts AS cca 
INNER JOIN
(SELECT DISTINCT ClientAccount, SKAccount, SKDesc, 
    SKBase, SKBranch, ClientType, SKStatus, GFCID, 
    GFPID, Account_Open_Date, Account_Update
FROM          ClientsAccounts_IMPORT) AS ccai 
ON cca.Branch_Account = ccai.ClientAccount

Table definitions follow:

CREATE TABLE [dbo].[ExistingClientsAccounts_IMPORT](
    [AccountID] [int] NOT NULL,
    [SKBranch] [varchar](2) NOT NULL,
    [SKAccount] [varchar](12) NOT NULL,
    [SKName] [varchar](255) NULL,
    [SKBase] [varchar](16) NULL,
    [SyncStatus] [varchar](50) NULL,
    [SKCCY] [varchar](5) NULL,
    [ClientType] [varchar](50) NULL,
    [GFCID] [varchar](10) NULL,
    [GFPID] [varchar](10) NULL,
    [SyncInput] [smalldatetime] NULL,
    [SyncUpdate] [smalldatetime] NULL,
    [LastUpdatedBy] [varchar](50) NOT NULL,
    [Deleted] [tinyint] NOT NULL,
    [Branch_Account] [varchar](16) NOT NULL,
    [AccountTypeID] [int] NOT NULL
) ON [PRIMARY]


CREATE TABLE [dbo].[ClientsAccounts_IMPORT](
    [NEWClientIndex] [bigint] NOT NULL,
    [ClientGroup] [varchar](255) NOT NULL,
    [ClientAccount] [varchar](255) NOT NULL,
    [SKAccount] [varchar](255) NOT NULL,
    [SKDesc] [varchar](255) NOT NULL,
    [SKBase] [varchar](10) NULL,
    [SKBranch] [varchar](2) NOT NULL,
    [ClientType] [varchar](255) NOT NULL,
    [SKStatus] [varchar](255) NOT NULL,
    [GFCID] [varchar](255) NULL,
    [GFPID] [varchar](255) NULL,
    [Account_Open_Date] [smalldatetime] NULL,
    [Account_Update] [smalldatetime] NULL,
    [SKType] [varchar](255) NOT NULL
) ON [PRIMARY]

The error message I get is: Msg 8152, Level 16, State 14, Line 1 String or binary data would be truncated. The statement has been terminated.