DDE is no longer supported by Microsoft Excel, but you are able to use the DDE feature with another program called Open Office. Open Office is similar to Microsoft Word, as it offers its users the ability to manipulate spreadsheets, word documents, and many other office related files. 


However, Open Office is free. You can download Open Office from https://www.openoffice.org/.


Once you download and install Open Office, you will want to run the DDE feature similar to how you run the RTD feature in Microsoft Excel. Unlike the RTD feature, however, you will need to change the settings for Quotestream to send data into Open Office to to "RTD Mode: DCOM". 


To change the setting, 


1) Please open Quotestream. 

2) Next, go to the "File" menu and click on "Preferences". 
3) In the bottom-right corner of the "Preferences" screen, you will see "RTD Settings". Please switch the RTD setting to "DCOM".


Now, please shut-down Quotestream. Re-open Quotestream in "Administrator" mode by right-clicking on the desktop icon and selecting "Run as Administrator".


Next, open the Open Office program in Administrator mode, by right-clicking on the Open Office icon and taking a similar approach as in the step above.


Now that both of these programs are running, data should feed into Open Office from Quotestream. Select "Spreadsheets" on the main Open Office introductory menu, which appears when you open the program. You will see a spreadsheet similar to Excel. Enter commands in the spreadsheet, as you would with the RTD feature. 


For example, enter:

=DDE("quotestream";"AAPL";"Last")