I loaded ZT280_E7_1f_C71_Android2.3_1110_GO_V1.6\ZT280_E7_1f_C71_Android2.3_1110_GO_V1.6 > this is OS 2.2.3 >google<
I did create a folder zt-update and extracted the files to it.
took me awhile to find this fix many trys ,with zt-update not found. with black screen.
push the sound buttom to change boot modes.
Gps still doesn't work.
Insert a standard SD card into your computer’s media reader.
2. Download this file and save it to the root of the SD card, not in any folder.
3. Do not extract the contents of the ZIP file, leave it as a ZIP archive.
4. Do not rename the file. Do not allow your browser to change the name of the file. If necessary, change it back.
5. With the Tablet powered off, press and hold the volume up button (keep holding), then press and hold the power button at the same time.
6. Keep holding both buttons, the screen will read he Tablet first, and then the Android robot and software package icons will appear on the screen with a progress bar.
7. You may now release the buttons and allow the process to complete.
8. When done, the tablet load will reappear and the unit should then load normally.