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GS1 128 for USPS printed label certification

I am working with USPS to get certified so our company can start printing our own tracking labels using the Aspose Barcode lib. But their test results show that the barcodes I've generated have a Code B and Code C Start and Stop in the barcode (even though I've not specified it in my code). Below is my source code (the code text is (420)921170000(93)14890144258200146810 below is the response from USPS

Not allowed with USPS Code 128
Not allowed with USPS Code 128

Source code is shown below...

Dim lic As New Aspose.BarCode.License
Dim sPN As String = sBarCode
Dim sFile_Barcode As String = "c:\temp\barcode_temp_" & sPN & ".jpg"


'Create the 1D bar code
br.CodeText = sPN

br.CodeTextColor = System.Drawing.Color.White
br.CodeLocation = Aspose.BarCode.CodeLocation.None

br.SymbologyType = Aspose.BarCode.Symbology.GS1Code128

br.BarHeight = 20

br.xDimension = 0.6F
br.GraphicsUnit = System.Drawing.GraphicsUnit.Millimeter

br.Save(sFile_Barcode, Aspose.BarCode.BarCodeImageFormat.Jpeg)

Hi Gerry,

Thank you for contacting support. We’re working over your inquiry and will get back to you soon.

Hi Gerry,

We need to investigate it. We have logged an investigation under ticket id BARCODENET-34097 in our issue tracking system. We’ll let you know once we get a response from our development team. Please spare us a little time.

Hi Gerry,

Thank you for being patient. Please confirm that which version of Aspose.BarCode for .NET are you using? The latest version is 6.7.0. If you are using an older version, then please use the latest version and let us know how it goes on your side.

Please refer to the download page:

As I understood, USPS wants to use only CodeA encoding even if it breaks standard?

They want the code b and code c removed. And no code a either. I just need a way to tell the barcode library no code a , no code b , no code c.

I looked at my barcode library it’s version 6.4 dated 6/26/2014. Perhaps the newer version addresses this issue?

Please let me know if version 6.7 addresses the issue. Because I don’t have a way to test the presence of code b and code c in the barcode

Hi Gerry,

Thank you for the reply. We’re in communication with our development team and will get back to you soon. Please spare us a little time.

Lets be clear. Here is code 128 standard

This code has three different encoding mode:

So, every code 128 barcode MUST have a least one start symbol Start Code A/B/C. Without this it is impossible to create code.

Also this barcode has CODE A/B/C code which can switch encoding data to different type “on a fly”. But we don’t use this with GS1Code128. So, this problem just cannot be.

So I still haven’t understood what they really want.

Can you add to this thread image of barcode which has problem as USPS thinks?

yes i think there is some confusion on my part as well. The acronyms used by the post office are rather vague and confusing. I was reading another barcode vendors web site and they stated that the USPS barcode requirement is for a “EAN-128” barcode which I believe is another/different barcode in your library. I think I may have been using the wrong barcode all together. But again in the USPS documentation they clearly state it is to be “GS1 128” so you can see where my confusion has started. Can you confirm that the EAN-128 barcode does not have code b and code c? If so I will use it to create my next set of samples. Appreciate all your help and sorry for all the confusion. Thanks again.

just to add a little more detail information. Here is what another vendor has on their site. I have omitted (blankblank) any reference to the vendor and it’s product.

“The United States Postal Service uses the EAN-128 barcode (also known as Code 128 and GS1-128) for special services such as delivery confirmation. When used for the USPS, the blankblank font provided in the Code 128 blankblank Package and the blankblank Package should be printed at 16 points, which will produce a height of .75” and an X dimension of .013" as required."

attached is a sample barcode sent to USPS for testing. And the second file (s129.pdf) is the test results sent back by USPS showing the error in structure (code b and code c were detected).

attached is the barcode construct specifications given by USPS.

Hi Gerry,

I have intimated Alexander to respond to this. We’ll get back to you once we receive a response from him. Please spare us a little time.

Yes, problem exists. There are really CodeB+CodeC in barcode which do nothing (mode changed to B them returned to C).

I think problem only with 6.4 version.

Try to update to 6.7 version.

Can you generate barcode with 6.7 version and add image as attachment to check it. This can help to detect problem if it exists.

attached is my new barcode image using version 6.7, please let me know if code b and code c are no longer present. Thank you.

Yes, with this code, everything is ok. No Code A/B/C switching codes.

@gerryjam73 - Did you ever get this to work? I’m also trying to create the IMpb and I am having several issues with Aspose.Barcode.


You may please give a try to our latest release and if find some issue, please create a new thread along with the runnable sample code and template file for our reference. We will test the scenario and provide assistance accordingly.