TntMPD has always had a limit of 25 characters on the organization code stored internally in the database. TntMPD 3.0 now reports when the organization code is too long. This might seem like a nuisance, but in the past this was a bug and caused some unexpected behaviors in hard to diagnose ways.
If you receive this bug, you should report it to your organization's IT department. I'll show below the exact code they can change to fix this bug.
While you wait for your IT department, if you can edit the *.tntmpd file you download (in Notepad for example) so that the line starting with "Code=..." has a subsequent code less than or equal to 25 characters long, you'll be able to import the file.
For example, if the line in your file says:
edit to say:
Then you'll be able to import the file. In TntMPD 3.0.7 or later, it can be any code less than 25 characters. In TntMPD 3.0.6 it must be exactly the first 25 characters of the original code (like in the example).
Server Bug Fix
In Visual Studio, find the file home/tnt.aspx.cs.
It contains these lines that set the code:
TntMPD TntExporter = new TntMPD();
TntExporter.Org_Name = clientName;
TntExporter.Org_Abbreviation = clientCode;
TntExporter.Org_Code = clientCode + "-Missionary_eConnect";
Add this afterwards:
if(TntExporter.Org_Code.Length > 25)
TntExporter.Org_Code = TntExporter.Org_Code.Substring(0, 25);
Build and publish.