Coby 7033 Bootlooping

I tried the signed file that you provided Vampirefo, however still getting the same error message complaining about being "Unable to verify whole file signature". I checked the MD5 hash of the file right after download, and again after transfering to the SDcard, hashes matched. Even downloaded the file from another computer (MD5 hashes still matched), just to make sure something on my PC wasn't messing with the file.

It seems that this model doesn't have fastboot (well any mode of accessing other then through ADB), which rules out any possible attempts to connect to the device with it in it's current state. I tried every possible combination with the buttons that could possibly have been used, only managed to enter recovery mode and VDfu mode (which i'm assuming is for using the Vortex Flash utility).
 
Hello one and all. I'm new to these forums but have been sifting through the past few days because I have the same problem as OP. I rooted the mid7035 and got a system dump as per the instructions of this forum. When i tried to load Gapps with ABD and change the file permission is when the tablet started bootlooping the COBY logo. Ican still get into recovery 3e and access VDfu drive ( whatever that is). Also, ADB recognizes my device but says it is offline because the tablet automatically switches usb debugging off when a reboot occurs.
This leaves me with few options, if i'm not mistaken. 1) I could use livesuite to flash stock img( although not recommended by this forum), 2) according to OP I can use Vortex flash utility to flash stock img through the VDfu drive, or 3) i could use ubuntu on a usb stick and update the device with ADB using no drivers. I have only found instructions on the livesuite method so I might have to go that route. Any opinions? Thanks for all the info thus far everyone.

PS is there a way to put a signature on my system dump files so as to work around the recovery3e "file verificaiton failed" glitch?
 
I don't know why Coby would change their signature on the 7033, oh well if it doesn't work then it doesn't work.

care to try this file, it won't do anything to your 7033, other than check signature.

unroot_telechips_signed.zip
Yep, that file gave the same "Unable to verify whole file signature". It's really looking like Coby (or the manufacturer that Coby used) has managed to change the sigs for the 7033.

Hello one and all. I'm new to these forums but have been sifting through the past few days because I have the same problem as OP. I rooted the mid7035 and got a system dump as per the instructions of this forum. When i tried to load Gapps with ABD and change the file permission is when the tablet started bootlooping the COBY logo. Ican still get into recovery 3e and access VDfu drive ( whatever that is). Also, ADB recognizes my device but says it is offline because the tablet automatically switches usb debugging off when a reboot occurs.
This leaves me with few options, if i'm not mistaken. 1) I could use livesuite to flash stock img( although not recommended by this forum), 2) according to OP I can use Vortex flash utility to flash stock img through the VDfu drive, or 3) i could use ubuntu on a usb stick and update the device with ADB using no drivers. I have only found instructions on the livesuite method so I might have to go that route. Any opinions? Thanks for all the info thus far everyone.

PS is there a way to put a signature on my system dump files so as to work around the recovery3e "file verificaiton failed" glitch?
Welcome to the forums.

I'm curious as to what you've done to cause the same issue (besides installing Gapps...lol), mainly because I'm trying to figure out if it's from where I changed the permissions on the /system folder, or if it's where I forgot to copy over the other folders (I didn't notice it until this morning messing with the tablet some more, that the gapps folder I copied only had the .apk files, it was missing the libs and other folders). As far as the other methods of recovery go, from what i've been seeing from the flash utility, there's a file (.pak file) that is needed, and i'm not 100% sure that the utility can do just the /system folder (which would fix the issue). There's no real information regarding the tool on these tablets.

As far as the signature goes, you can try using the SignAPK.jar file, with the test keys (or your own private key) and see if that get around the file verification issue on the 7035.
 
Ok, Ubuntu can see the device yet returns that I have insufficient permissions to do anything on the device. Windows recognizes the device, yet lists it as offline (only in recovery, normal mode doesn't show at all). So it seems that the device isn't totally screwed.

And I can forget about trying to pull the internal SDcard and fixing that way, as the 7033 doesn't contain an internal SD, all that's there is the CPU (ViMicro VC 0882 CPU) and two Hynix memory chips (couldn't determine the part no's, way too small of print). If I can get a backup from the VDfu interface (which I need to find a tool that can read from the interface, the flash tool can only write to it), I should be able to fully repair the device.

**EDIT** I forgot to run the ADB as su... Doing that stopped the insufficient permissions error, and now gives me the same error as windows (device is offline).

**EDIT #2** VDfu + Flash Tool is a no-go. Without having an exact flash from Coby, the device just reboots and goes right back into VDfu mode, and the utility says that the flashing failed (connection lost). Looks like ADB and SD are the only ways to get this fixed unless Coby decides to answer my emails (since they will not provide any help over the phone).
 
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Think i'm going to get some sleep here before I end up trying to fix this thing redneck style.
 
Ok, found out that the VDfu mode and Vortex flash utility error wasn't due to the device needing a special flash file from Coby. The utility seems to look for a particuar partition size for /system and if it can't find it error's out (8 hours of trying to get the device working with 3 different OS's will start to wear on you). I can flash just the /system folder, which is a good thing, however it requires knowing details of the NAND chips...

Hopefully Coby is nice enough to provide me the details (and possibly the flash files) to get the device fixed, and not tell me "the device has been discontinued and we can no longer provide support for it", like their customer service rep did when I called for the 5th time since the 17th.
 
Finally heard back from Coby this afternoon via email. Apparently their technical support staff has the reading comprehension of a 5 yr old, or they don't actually read the emails, because I got a copy and paste reply for the "Master Reset" procedure (which I listed in the original email as being done several times at that point). Sent back another email and attached a link to a video of me doing the procedure and it still hanging on the "Android" logo (3 hour timespan). Hopefully the response will be faster since this is getting replied directly to a tech, and they can help without sending it back.
 
Well, it's official, it's gotta get sent back in. Apparently Coby will not release any of their firmware images for the flash utility (damn, no easy made custom rom).
 
I don't know why Coby would change their signature on the 7033, oh well if it doesn't work then it doesn't work.

care to try this file, it won't do anything to your 7033, other than check signature.

unroot_telechips_signed.zip

Excuse me for reviving this old thread, but investigating in the forum with a similar problem (boot loopin) I found this post and tried the unroot_telechips zip that you psted and applied to a Coby MID1024-8 which is (almost) bricked and found that it worked!!, it is the only zip that didnt show the verification error in recovery mode (3e): Can you explain me how you signed it please? (With which program and certs?). I have tried android-sign and Auto-sign but always the same error. In this case it passed. This would help me a lot in order to recover my Coby since there is no other possible way to have access to the tablet. Thanks

Edit Sorry my tablet is MID1042-8
 
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I have a 7033 with the same exact (as described) problem/s. Any updates on what you might have found as far as a way to unbrick/unsoftbrick? Vampire's been looking at a way to overcome this one, via external/bootable SD card. Not to run, but to at least get a working recovery that will allow us to get by the signature hurdle that the stock recovery has in the way. Here's a link to the thread:

Thread: AMLogic Tablets, 7033, 7035, 7065, 7060, and So On: Repair Tablet from SD Card (original post)
 
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Another possibility I ran across.

Possible work around: (using ADB running under Linux)

#!/system/bin/sh
echo " "
echo "Wating for device..."
./adb wait-for-device
echo " "
./adb -d shell stop
./adb push mycwmfix.zip /sdcard/mycwmfix.zip
./adb reboot recovery


-------------------------------------------------------

#!/system/bin/sh
echo " "
echo "Waiting for device..."
./adb wait-for-device
echo " "
./adb -d shell stop
./adb -d shell su -c "mount -o remount rw /system"
./adb push framework-res.apk /system/framework/framework-res.apk
./adb -d shell chmod 644 /system/framework/framework-res.apk
./adb push SystemUI.apk /system/app/SystemUI.apk
./adb -d shell chmod 644 /system/app/SystemUI.apk
./adb reboot

------------------------------------------------
I'm not certain who the author is, or who to credit for the above, but I found it at this link:

[h=1] Link: How to recover from a bootloop[/h]


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Possibly gives enough time (freezes things at boot, so-to-speak) to access the sdcard and make changes without root/USB debugging mode set. I'm not positive if this would work, but it is a possibility.
 
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If you have a Coby MID7033 that's been sitting gathering dust sitting in a corner etc, because it's stuck in a bootloop/bricked, you might want to pull it out, and dust it off. Then be ready. Check out this thread:

[h=1]Thread: [URL="http://www.androidtablets.net/forum/coby-generation-3-development/62622-amlogic-tablets-7033-7035-7065-7060-so-repair-tablet-sd-card-15.html"]AMLogic Tablets, 7033, 7035, 7065, 7060, and So On: Repair Tablet from SD Card[/URL][/h]
Thread number #142!!! Be patient, because Vampirefo.'s working diligently and devoting A LOT of his precious time to helping you with your otherwise dead tabs!(warm smilz)
 
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