1) Double-click UOSV2.exe.

2) If this logo is shown, UOSV2 is working in English. Read 3).

If this logo is shown, it's working in Japanese.
This problem is caused If user's Windows is not USA eddition.
Please change Regional setting of Windows while you're using UOSV2.
As follows:
a. Click [Start] - [Settings] - [Control panel] - [Regional options(or
Regional settings)] - [General] - [Language]
2. Select [English]
3. Click below [Locale (or Country)]
4. Select [USA]
5. Reboot
3) This window is shown.

Click Yes.
If problem happens, follow as below.
1) Restart UOSV2.
2) This window is shown.

Click No.
Select client.exe in Ultima Online folder.