OdbcConnection Open working for one user but not the other one SqlAnywhere

My C# progrm works for most users but not for all of them anymore.

For some users the ODBC connection won't open.

It use to work with those user but it has stopped for some reason.

The code is:

const string connectionStr="Dsn=db01;Uid=user1;Pwd=123;"

using (OdbcConnection conn = new OdbcConnection(ConnexonGCMEQ.connString))
{
      MessageBox.Show(conn.ConnectionString); 
      conn.Open();
}

I had a look at the db01 connection in ODBC data source administrator and it's identical. The test connection button also works. In fact annother app uses the same connection and still works fine.

I activated odbc tracing and here is the result(I can't figure out how to make something out of them)

243            1af0-1634    EXIT  SQLAllocHandle  with return code 0 (SQL_SUCCESS)
        SQLSMALLINT                  2 <SQL_HANDLE_DBC>
        SQLHANDLE           0x052CFB50
        SQLHANDLE *         0x028E3C34 ( 0x052D1E30)

0243            1af0-1634   ENTER SQLSetConnectAttrW 
        SQLHDBC             0x052D1E30
        SQLINTEGER                 103 <SQL_ATTR_LOGIN_TIMEOUT>
        SQLPOINTER                15
        SQLINTEGER                  -5 

0243            1af0-1634   EXIT  SQLSetConnectAttrW  with return code 0 (SQL_SUCCESS)
        SQLHDBC             0x052D1E30
        SQLINTEGER                 103 <SQL_ATTR_LOGIN_TIMEOUT>
        SQLPOINTER                15
        SQLINTEGER                  -5 

0243            1af0-1634   ENTER SQLDriverConnectW 
        HDBC                0x052D1E30
        HWND                0x00000000
        WCHAR *             0x68792430 [      -3] "******\ 0"
        SWORD                       -3 
        WCHAR *             0x68792430 
        SWORD                       -3 
        SWORD *             0x00000000
        UWORD                        0 <SQL_DRIVER_NOPROMPT>

0243            1af0-1634   EXIT  SQLDriverConnectW  with return code -1 (SQL_ERROR)
        HDBC                0x052D1E30
        HWND                0x00000000
        WCHAR *             0x68792430 [      -3] "******\ 0"
        SWORD                       -3 
        WCHAR *             0x68792430 
        SWORD                       -3 
        SWORD *             0x00000000
        UWORD                        0 <SQL_DRIVER_NOPROMPT>

        DIAG [08001] [Sybase][ODBC Driver][SQL Anywhere]Erreur de connexion : Une erreur est survenue lors de la tentative de connexion via TCPIP (-832) 

For the working user:

0243            2210-3550   EXIT  SQLAllocHandle  with return code 0 (SQL_SUCCESS)
        SQLSMALLINT                  2 <SQL_HANDLE_DBC>
        SQLHANDLE           0x05F627F0
        SQLHANDLE *         0x034F6280 ( 0x05F62870)

0243            2210-3550   ENTER SQLSetConnectAttrW 
        SQLHDBC             0x05F62870
        SQLINTEGER                 103 <SQL_ATTR_LOGIN_TIMEOUT>
        SQLPOINTER                15
        SQLINTEGER                  -5 

0243            2210-3550   EXIT  SQLSetConnectAttrW  with return code 0 (SQL_SUCCESS)
        SQLHDBC             0x05F62870
        SQLINTEGER                 103 <SQL_ATTR_LOGIN_TIMEOUT>
        SQLPOINTER                15
        SQLINTEGER                  -5 

0243            2210-3550   ENTER SQLDriverConnectW 
        HDBC                0x05F62870
        HWND                0x00000000
        WCHAR *             0x5B3B2440 [      -3] "******\ 0"
        SWORD                       -3 
        WCHAR *             0x5B3B2440 
        SWORD                       -3 
        SWORD *             0x00000000
        UWORD                        0 <SQL_DRIVER_NOPROMPT>

0243            2210-3550   EXIT  SQLDriverConnectW  with return code 0 (SQL_SUCCESS)
        HDBC                0x05F62870
        HWND                0x00000000
        WCHAR *             0x5B3B2440 [      -3] "******\ 0"
        SWORD                       -3 
        WCHAR *             0x5B3B2440 <Invalid buffer length!> [-3]
        SWORD                       -3 
        SWORD *             0x00000000
        UWORD                        0 <SQL_DRIVER_NOPROMPT>

0243            2210-3550   ENTER SQLAllocHandle 
        SQLSMALLINT                  3 <SQL_HANDLE_STMT>
        SQLHANDLE           0x05F62870
        SQLHANDLE *         0x034FA360

It seems to be related to the user and not the computer. Does the suer need special permission on a folder?

The user also has acces through a database browser with the same connection string.

update: when the app is installed in an other folder(on the same shared drive) the user can run it. What folder acces deos odbc driver need?