Upgraded to 1903 with build 18362.30 without any glitch.
So, 17763."402" seems to be OK for ja-JP editions.

My RP ring build 17763.402 (x64 pro ja-JP) has not received KB4493510 yet and received KB4490481 on March 22 (JST). I don't know what to do right now, but it is not very comfortable to see the build...

It appears depending on many factors. As I already posted three days ago, the workarounds (key strokes) change time to time.

Thank you very much for the suggestion. I could finally find a way to enter the UUPtoISO option, but it was not so straightforward.

I had to use not only ALT but also CTRL along with the number...

Did anyone try UUPtoISO software on Build 16193?
In my case it started as usual and accepted the UUP file location info by pasting. But it does not take any keyboard input and make buzz sound at...

Now that I could create ISO and upgraded 15063 to 16170, I do simply appreciate and admire the most dependable tool.

It works perfect even with Japanese versions and I did successfully upgrade my 15048 to 15055 without any problem.
Kari, SlicEnDice and other active people are very much appreciated for this great...