We'll sometimes things go wrong when you experiment with different applications (.apk) especially when you root and put unknown applications in the /system/app folder.
After many, many months of a stable working Sylvania SYNET7LP I become a little to adventurous an attempted to get Google Calendar working by copying some apk files from another infoTMIC powered tablet. I copied these three apk's to the /system/app folder after gaining root. I changed permissions and properties to match to the application in the folder.
Feeling confident I turned off the tablet and turned back on and after the initial infoTMIC logo the SYLVANIA logo popped up and stayed on the screen. The animated SYLVANIA logo never appeared, oh no, the tablet was stuck. Easy answer, "factory reset (three finger method)" but guess what appeared?
Are you kidding, this tablet has NO "recovery image" how can this be. I've done this dozens of times before over the last 6 months. Oh how easily I forgot, after sending various tablets back to Digital Gadgets Customer Service for repair this one has actually been functioning and I hadn't had to factory reset.No recovery image is found, try recover from SD
So what do I do? Manually update with one of the six (6) known 220.127.116.11 infoTM Update Wrap (.ius) files? Which one? Is anyone better than the others? No way for me to tell? At least I knew this tablet's Hardware ID "hwver" as I recommend anyone finding out immediately or after getting it back from Customer Service, since they are ofter swapped out.
Comparing the "/system" folders of beta4 to beta5, [which where obtained by exporting ADR_AS image "zSYS.img" with vio's IusEdit_0.41 then removing the uImage header, extracting the gzipped system.img archive and finally "Extracting contents of system.img ... " using HTC Android Kitchen by dsixda (xda-developers.com)], I discovered they were exactly the same. Comparing 18.104.22.168.2.2 "/system" folder to beta5 revealed some differences mostly related to Busybox commands. So which one? I decided upon beta5 based on previous discussions surrounding Busybox issues, no other reason.
However, performing a "manual update" seemed like overkill as someone else also noted. Using a PC analogy, reinstalling the BIOS, and the operating system, and updating all the drivers just to get a working tablet seems unreasonable for a simple electronics device.
So to the point of this post.
Instead I decided to use the knowledge gained from all the posts related to updating, development, and recovery and came up with this approach. Way back, the initial update method for other infoTMIC tablets was to use WinHex to "Create bootable SD card" by using the "Disk Tools" to "Clone Disk" with a raw image file "aben.start_sector.001". Upon creating the Clone Disk, the 705 MB partition is formatted FAT 32 with the Format Options - Quick Format. Then on the newly formatted partition an "android" folder is created. So after doing all this, and reviewing their procedure, the files added to the folder included zSYS.img which we've learned is the "recovery" image extracted initially from the InfoTM Update Wrap (.ius) file. Using vio's IusEdit_0.41 I exported ADR_AS image and saved as "zSYS.img" in the "android" folder on the bootable SD card.
With the tablet turned off, I inserted the "bootable SD card" and crossed my fingers. Upon turning on, the tablet displayed -
Booting from SDUpdating Image AndroidBurn file system finishedRebooting the tablet, I was returned to the stuck SYLVANIA logo. What was I thinking? I was burning the "recovery" image not a new file system. So I turned off the tablet by using the stylus to push the "reset" button. This time I applied a "factory reset (three finger method)".Take off SD and reboot.
Getting recovery image ...Extracting recovery data ...Burnning file system ...Note: Their mispelling, not mineRecovery OK!The tablet restarted - infoTMIC logo, SYLVANIA logo, miniturized animated SYLVANIA logo, "Touch crosshair to calibrate" screen. After calibration, the locked Home Screen appeared. Success!System will boot normally in %d seconds ...
Successful recovery using only zSYS.img instead of having to manually update with InfoTM Update Wrap file containing multiple images including U0 "u-boot-nand.bin", Ramdisk, Kernel, Userdata.
However, not a complete success. Why is the animated logo so small, and after turning Wi-Fi on getting "Unable to scan for networks". Now going to try the method again with the zSYS.img from 22.214.171.124.2.2 and see if any better succes.
So to cut a long story short - if after experimenting or if something goes wrong requiring a "factory reset (three finger method)" and you receive the "No recovery image is found, try recover from SD" message, knowing the Hardware ID 'hwver" and having a recent InfoTM Update Wrap (.ius) file for the tablet, you can use vio's IusEdit_0.41 to export ADR_AS image "zSYS.img" from the file, then use the WinHex "aben.start_sector.001" method to create a "bootable SD card" and copy zSYS.img into an "android" folder on the card. Boot the tablet to burn the "recovery image", then use the "factory reset (three finger method)" to restore.
For those that can't create the "bootable SD card" you could easily burn an exported zSYS.img using the InfoTM Update Wrap Tools (IUW.exe) with "USB mode: Expert burn" with "SYSBACK" checked.
It's "Recovery" it's just not easy!
Note: This will NOT "unbrick" a tablet when the incorrect InfoTM Update Wrap (.ius) has previously been burned as the U0 "u-boot-nand.bin" image controls the communication with the tablets board. This is only for restoring the file system.
Update - The zSYS.img exported from 126.96.36.199.2.2.ius restored the animated logo to normal size and resolved the Wi-Fi scanning issue.