Hi Malek;

  Build 2728 is PB2019R3. In this revision, Appeon decoupled the IDE from the PB runtime. So once you migrate the older PB App, please make sure that you ...

• Select the menu TOOLS => System Options => General ... and make sure that the Run Time version is set to 2728 
• Open your PB App's "Project" object(s) and in the "Run" folder, also make sure that the runtime version is set to 2728

HTH

Regards ... Chris

Hi Malek，

First I suggest you open your Application Object by Edit Source and check if the appruntimeversion inside is "19.2.0.2728".

global type test from application
string appname = "test"
string themepath = "C:\Program Files (x86)\Appeon\PowerBuilder 19.0\IDE\theme"
string themename = "Do Not Use Themes"
boolean nativepdfvalid = false
boolean nativepdfincludecustomfont = false
string nativepdfappname = ""
long richtextedittype = 2
long richtexteditx64type = 3
long richtexteditversion = 1
string richtexteditkey = ""
string appicon = ""
string appruntimeversion = "19.2.0.2728"

Next, open your PBT file in Notepad and check if the appname value has any upper-case letter. If any, change it to lower-case then verify if the issue is gone.

Save Format v3.0(19990112)
appname "test";
applib "test.pbl";
liblist "test.pbl";
type "pb";

You can also try creating a new PBT file for your application in New -> Target -> Existing Application then see if the issue is gone.

If the issue remains, please upload your Application Object and PBT file for us to check.

Regards,
Ken