diff --git a/src/libraries/System.Diagnostics.Process/src/Microsoft/Win32/SafeHandles/SafeProcessHandle.Unix.cs b/src/libraries/System.Diagnostics.Process/src/Microsoft/Win32/SafeHandles/SafeProcessHandle.Unix.cs
index e78f8c8acf8cde..258c5edbc54c8a 100644
--- a/src/libraries/System.Diagnostics.Process/src/Microsoft/Win32/SafeHandles/SafeProcessHandle.Unix.cs
+++ b/src/libraries/System.Diagnostics.Process/src/Microsoft/Win32/SafeHandles/SafeProcessHandle.Unix.cs
@@ -374,7 +374,7 @@ private static SafeProcessHandle StartWithShellExecute(ProcessStartInfo startInf
             if (verb != string.Empty &&
                 !string.Equals(verb, "open", StringComparison.OrdinalIgnoreCase))
             {
-                throw new Win32Exception(Interop.Errors.ERROR_NO_ASSOCIATION);
+                throw new Win32Exception(Interop.Errors.ERROR_NO_ASSOCIATION, SR.Format(SR.UseShellExecuteVerbNotSupported, verb));
             }
 
             // On Windows, UseShellExecute of executables and scripts causes those files to be executed.
@@ -405,7 +405,7 @@ private static SafeProcessHandle StartWithShellExecute(ProcessStartInfo startInf
             }
 
             // use default program to open file/url
-            filename = Process.GetPathToOpenFile() ?? throw new Win32Exception(Interop.Errors.ERROR_NO_ASSOCIATION);
+            filename = Process.GetPathToOpenFile() ?? throw new Win32Exception(Interop.Errors.ERROR_NO_ASSOCIATION, SR.UseShellExecuteNoOpenProgram);
             string[] openFileArgv = ProcessUtils.ParseArgv(startInfo, filename, ignoreArguments: true);
 
             SafeProcessHandle result = ForkAndExecProcess(
diff --git a/src/libraries/System.Diagnostics.Process/src/Resources/Strings.resx b/src/libraries/System.Diagnostics.Process/src/Resources/Strings.resx
index df17778b76ff0a..ee9ffac8b7ab60 100644
--- a/src/libraries/System.Diagnostics.Process/src/Resources/Strings.resx
+++ b/src/libraries/System.Diagnostics.Process/src/Resources/Strings.resx
@@ -390,4 +390,10 @@
   <data name="Argument_InvalidProcessId" xml:space="preserve">
     <value>The callback must return a positive process ID for the newly created process.</value>
   </data>
+  <data name="UseShellExecuteVerbNotSupported" xml:space="preserve">
+    <value>The verb '{0}' is not supported for UseShellExecute on this platform. Only the default verb (an empty string or "open") is supported.</value>
+  </data>
+  <data name="UseShellExecuteNoOpenProgram" xml:space="preserve">
+    <value>No program was found to handle opening files or URLs with UseShellExecute on this platform. Ensure one such as 'xdg-open' or 'open' is installed and available on the PATH.</value>
+  </data>
 </root>