Kobo 1st gen screen frozen

[Pitbull Poet]

I have an original (non-wifi) Kobo ereader, which I bought just over a year ago at an Indigo store in Toronto. (I'm living in the US and don't have easy access now to Indigo/Chapter stores.) I've been using my ereader without problem all year until several days ago. I've been running the current firmware for many months. The screen is now frozen and divided vertically in half, the left half lighter gray than the right with the splash screen that one sees when powering on the Kobo in light gray. I had just charged the my ereader using the provided cable, a usb power adaptor, and an ac outlet. When the power light turned blue, I unplugged my ereader without choosing either "Manage my books" or "Continue reading." As expected, my ereader returned to the cover the book I was currently reading. When I then later powered my Kobo on, I got the expected splash screen with the Kobo logo in the middle. Then rather than loading, the screen froze in the configuration described above.

I have tried repeatedly to do a factory reset, using a paperclip in the hole on the back of the ereader. The power light turns red, then blue, then goes out, but the screen does not change. I've tried this 15-20 times.

I've tried pressing and holding the power switch for 8 seconds followed by a short press and release, as described in a Kobo faq. This has failed.

I've tried pressing the power button for up to minute. This has failed.

I've plugged the ereader into my Mac via the usb port. The ereader neither appears on the Mac desktop nor the Kobo application, version 2.0.3. The ereader appears to be charging (red light is on), but screen is fozen in above configuration.

Does anyone have ideas about how to sole this problem? I've also emailed Kobo CS.