Note: Read this guide fully before beginning. Although effort has been put in to ensure all procedures are safe, you are responsible for what you do with this information.
Here is the discussion thread where the process was developed: See here.
There have been several instances of people having problems with A1 and A1107 devices. This guide explains how to fix any software issue, including those that "brick" the device, or stop it from booting up at all, by restoring the tablet to a completely stock factory state. It can also be used to safely upgrade a Gingerbread A1 to Ice Cream Sandwich, by using the A1107 image that corresponds to the storage space that your device has.
Be aware that this procedure will erase all data on your device.
There are four different versions of this procedure:
2. Browse to select the image file that you downloaded, and select your SD card device from the drop down menu. Check that the MD5 Hash of the file matches the one given above by ticking the "MD5 hash" box.
3. Select the "Write" button to write the image to the SD card.
1. Check the MD5 hash of the file you downloaded matches the hash provided above:
md5sum <image name>
2. Write to the SD card using dd from the command prompt:
dd if=<image name> of=/dev/<device name> bs=1M
where <image name> is the image file you downloaded, and <device name> is the name of the SD card reader (e.g. mmcblk0, etc.). There is no progress bar - you might have to wait a while for it to complete.
Using the bootable SD
1. Power off your A1 and insert the SD card.
2. If the battery is below 30%, you will need to charge up to at least 30% for the procedure to work. If your A1 is totally dead, try plugging in the power cable and holding down the power button for 10 seconds then letting go, then holding for 10 seconds again, repeating until you see the green charge indicator on the screen - let go of the button as soon as you see this.
3. Boot the A1 into recovery mode from the SD card, by holding down the volume down key whilst turning on the power. Keep holding the volume down key until a menu entitled "CWM-based recovery v22.214.171.124" appears. This menu is navigated with the up/down keys, and the power key is used to select.
4. Select "install zip from sdcard" then "choose zip from sdcard" then "part1.zip" then choose "Yes - Install part1.zip". You should shortly see a message telling you that writing part 1 succeeded.
5. Choose "+++++Go Back+++++", then "reboot system now". As soon as you select "reboot system now", start holding down the volume down key, so that the tablet will reboot into the recovery mode again.
6. When you are back at the menu, choose "install zip from sdcard", then "choose zip from sdcard", then "part2.zip", then "Yes - Install part2.zip". You should see several messages scroll up, and finally "Install from SD card complete."
7. Choose "choose zip from sdcard" again, then "part3.zip", then "Yes - Install part3.zip". You should again see the message that the install from SD card is complete.
8. Choose "+++++Go Back+++++", then "wipe data/factory reset" then "Yes -- delete all user data". When this is completed, you should see "Data wipe complete."
9. Remove the SD card and choose "reboot system now".
10. The system might hang on the first boot because it is slow to realise that the SD card has been removed - if the tablet doesn't boot up, hold down the power button for 10 seconds to turn it off, then turn it back on again.
If all has gone well, your tablet should now be in the A1 or A1107 factory state depending on which image file you used.
1. What's the difference between this procedure and doing "wipe data/factory reset" in recovery mode?
"Wipe data/factory reset" only formats the data and cache partitions. It doesn't restore the hidden partitions, the system partition, or format the internal SD card.
2. What's the difference between this procedure and installing an OTA?
An OTA installation restores some, but not all, of the hidden partitions, and it does not format the data partition or the internal SD card.
3. What is each part doing?
Part 1 restores the contents of all of the hidden partitions, which live in the first 48MB or so of the eMMC storage. Part 2 installs an OTA zip file. Part 3 formats the internal SD card.
4. I made the bootable SD card but it doesn't seem to work. Why?
Some SD cards just don't seem to work for booting the A1 from. Try another SD card - most class 4 cards seem to work.
5. There isn't a 2GB A1107 - what is that image for?
You can use it to install Ice Cream Sandwich on a 2GB A1. It installs the same hidden partitions as the 16GB version, but it has a partition table for the 2GB A1 that has been modified to fit the Ice Cream Sandwich system image.
6. Do I need to follow this procedure?
If you're not sure, make a post on Lenovo Forums describing the problem you're having. Someone may suggest that you need to follow this guide, or they might tell you to try something else first instead.
7. My tablet was sold as 16GB but has 2GB internal and 14GB internal SD memory. Do I select the 2GB or 16GB image?
Use the 16GB image.
8. Do I need to root the tablet before following this procedure?
No. Because everything runs directly from the SD card, the state of the internal storage on the tablet does not matter, so rooting is not necessary.
9. How would it be different if Lenovo had provided an OTA update to ICS for the A1?
An OTA update would preserve your data when updating to ICS. This procedure erases all data on the tablet.
10. If I install ICS on an A1, how do I go back to the factory-installed Gingerbread?
Follow this guide again, but use the A1 Gingerbread image on the SD card instead of the A1107 Ice Cream Sandwich image.
11. What do I do if I want to keep my apps and their data?
You can root the tablet and use Titanium Backup from the Play Store to backup apps and their data before following this procedure. You can backup other data on the internal SD card by plugging into a computer and copying across the files to your computer, or by using a file manager to copy files to an external SD card.
12. I've installed the ICS image and I have some feedback for improvements of this ROM...
That's great - you might start a thread on the Ideapad/Ideatab forums to discuss it, and Lenovo may notice and read it. However, please don't post feedback on the ICS ROM to the thread that discusses this guide ( this one: this one ) because that thread is only for support relating to the use of this guide - if everyone puts their ROM feedback there, the support-related posts will be drowned out and the thread will become difficult to navigate.
13. Can I just flash these images using the recovery I already have installed, instead of booting from the SD card?
No - once you flash part1.zip, the recovery image you did have installed will be overwritten by the stock one, and you won't be able to continue the process.
14. I flashed part1.zip, and now it won't boot into CWM-based Recovery v126.96.36.199 - what happened?
You probably weren't actually booting from the SD card, and you just used your installed recovery image to flash part1.zip. Try making the SD card again, or try again with another SD card, to see if you can get it to boot from SD. Then continue the process with part2.zip and so on.
15. I finished the process to install ICS on my GB A1, but now when I boot up it just gets stuck at the Android logo (and the installation of part2 may have said that it failed).
There was a problem with flashing part1.zip (maybe you forgot/didn't restart?). Start the process again. If part1.zip still fails to flash, post in the thread discussing this article with the details of your tablet and what you've tried so far.