I need to program my Samsung system idcs 28d to add a barge key or be able to barge into calls

Did you read the Manual?

Page 69/70 refers.

iDCS Keyset User Guide--12/09

Hardwire Telecom http://www.hardwiretelecom.com > pdfs > Sams...
Your iDCS keyset is the most visible part of your telephone system. No matter what model keyset you are using telephone calls are handled the same way. The 28D.
92 pages

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It is possible that the outside lines have been blocked in the programming of the Samsung IDCS 28D system. You can try the following steps to unblock the outside lines:

1. On a phone that is working, press the TRANSFER button and dial 200.
2. Enter your system password. If you don't know your system password, you may need to contact your phone system administrator or service provider.
3. Press 713 for "Line Block Release".
4. Press the button for the line that is blocked (in your case, all 4 lines).
5. The display should show "RELEASE OK" for each line that is unblocked.
6. Hang up the phone.

If this doesn't work, it is possible that the phone system may need further troubleshooting or programming by a technician.

https://www.fixya.com/support/t6055012-samsung_idcs_28d

Feature Access Codes - Samsung iDCS 28D User Manual

https://www.manualslib.com > ... > User manual
Samsung iDCS 28D Manual Online: idcs keyset, System Tones, Feature Access Codes. This User Guide Is Written Based On The Default Access Code For Using Sys- ...


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Mentioned in the manual in both links. Page 24 in the first. On the second press CTRL+F and type 'out of town' and press enter.

iDCS Systems Administration Guide - *Cape Communications*

http://www.capecomm.biz > images > iDCS_System...
PDF
modify some functions to better manage the iDCS office telephone system. ... phone to notify users with Display Phones that you may be out of town. This.
23 pages

DCS Compact Programming Section

http://www.telephonesystemsdirect.com > program
PDF
The diagram below illustrates the keys on an iDCS 28D and an iDCS 18D keyset that have special functions during programming ... OUT OF TOWN. 07. IN TOMORROW.
344 pages

^67 then dial the number. Test it out first by calling a phone of your own with caller ID. Also try turning off the "Show Caller ID" in the settings.

Assuming you have the programming manual: get into program mode- press transfer button then 800; enter passcode (default is 4321); press volume up button to get "enable" on LCD screen; press speaker button; press 722; press extension number you want to add VT to; press button number of phone you want the VT to be on; press button to left of round scroll button; press 8 on dial pad 3 times to get to V options; press up/down arrow until VT appears; press Voice mail group number (509, 519, 529, 5049)- depends on what model system you have; press button to left of round scroll button; finally, press transfer button. you're done.

From the Subscriber Services Menu, Press [#] [7] [1] ....you will then hear the old password XXXXX you will be able to change it...

The Manual for a typical Samsung iDCS system is available here....

http://www.samsungidcsphonesystems.com/pdf files/idcs 16/iDCS_16_user_ins.pdf