signature verification failed

I have the Iconia Tab 8 HD not FHD and I am having issues flashing update zips in recovery menu when I first got the tablet everything was fine I rooted it using a SuperSU.zip when I flashed in the CMW recovery menu through my SD card but after a week i got a notice of a new update(the splitscreen update) which I couldnt instal due to an error so I assumed it was due to me rooting the device so i flashed an update zip again to restore the tablet back to its stock rom after that the Splitscreen update installed correctly, then afterwards I wanted to REROOT my tab but when trying to I notice I couldnt boot into CMW recovery menu only a regular recovery menu with black and red font word coloring so then I tried to install the SuperSU.zip again to root the tablet except this time I got a Signature Verification error and E:Failed to verify whole-file signature in /cache/sideload/package.zip how do I fix this please help me!!!

So its impossible for me to even apply update.zip!

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IronFly

Sorry but we can't talk about rooting and unrooting devices here.

Sonicdue13

I'm not asking for all that I just want to know how to get rid of the signature verification failed error please!!!

IronFly

Sonicdue13 wrote:
I wanted to REROOT my tab but when trying to I notice I couldnt boot into CMW recovery menu only a regular recovery menu with black and red font word coloring so then I tried to install the SuperSU.zip again to root the tablet except this time I got a Signature Verification error and E:Failed to verify whole-file signature in /cache/sideload/package.zip how do I fix this please help me!!!
So its impossible for me to even apply update.zip!

Reroot and SuperSU.zip......

We can't talk about that here, sorry.

Sonicdue13

But this error doesnt just and have to pertain to flashing the supersu.zip its also a stock rom update.zip just incase anything goes wrong to my tablet then what that signature verification failed **** is still there, how do I fix it?