How to extract unique indices for time series Data?

Dear all, I am into following coding:

 > library(quantmod)
 > Data1 <- get(getSymbols("TCS.NS", from = as.Date("2008-01-01"), 
return.class = "zoo"))[,4]
Warning messages:
1: In zoo(cd, order.by = index(x), ...) :
some methods for ?zoo? objects do not work if the index entries in 
?order.by? are not unique
2: In zoo(rval, index(x)[i]) :
some methods for ?zoo? objects do not work if the index entries in 
?order.by? are not unique

Here, I guess there are some duplicated dates-index. Is there any 
function available to automatically extract unique indices ???

Thanks and regards,