If it still does not suit your requirements, kindly provide a sample Excel file containing your desired DateTime value applied (you may create the Excel file in MS Excel manually), we will check on how to do it via Aspose.Cells APIs.
Your advice is working, but I have string as “1.1:00:00” (forget to mention it)
I resolve problem:
cell.PutValue(new DateTime(1900, 1, 1, 0, 0, 0, 0, DateTimeKind.Local).Add(time));
It looks like your issue is sorted out now. Let us know with details, sample code and template file if your issue is not resolved or you have some other query or issue, we will be happy to assist you soon.