Dec 062015

How to upgrade Acer Iconia W4 820 with windows 10

After windows 10 release in July’ 2015, compatible devices with windows 7 and windows 8/8.1 are also eligible for windows 10 free upgrade. Acer Iconia W4 tab and many windows 8.1 based tablet are eligible for windows 10 upgrade. This guide can also be referred many other devices tablet / laptop preinstalled with Windows 8.1 single language with Bing 32 bit/64 bit.

Upgrading windows 10 on Acer Iconia w4 tab was the toughest task I faced till date compared to installing/ upgrading Windows on many desktop/laptops. The following are the difficulties faced during upgrading  Acer Iconia Tab  with Windows 10 –

  1. No windows 8.1 CD or recovery drive provided by Acer/OEM
  2. Windows key embedded inside BIOS, no easy access to see the keys
  3. Windows 8.1 Single Language with Bing ISO image is not available anywhere on the web, Microsoft not providing the support for recovery they asked to contact OEM and OEM ask charges even it is in warranty period
  4. Due to UEFI secure boot structure and GPT partition, it is not easy to install windows using CD or USB stick
  5. Only One USB port provided (Micro USB) that is also used for charging
  6. Windows installation media does not support touch input or Bluetooth keyboard/mouse without drivers.
  7. Drivers are not able to install without plugging the charger and how could one give command without mouse/keyboard connected.
  8. Windows 8.1 recovery partition not allows your you upgrade.

How to upgrade Acer Iconia w4 to windows 10

(Disclaimer – This is an unofficial guide for windows 10 up gradation, do it with your own risk and knowledge, this site or author not responsible for any damage or loss of data. You may lose your data, windows recovery partition or device may be completely unusable if something went wrong during process. Consult your concern support center/ service center if you have any doubt first.)

When Windows 10 upgrade release an icon appear in taskbar, prompted you to upgrade your PC. I tried with this windows app but after download two times it failed to upgrade and return back to previous version of windows 8.1 with some “Safe OS phase error”. Thereafter I downloaded windows ISO image from media creation tool for Windows 10 Single language 32 bit. After extracting it I have copied on my Acer Iconia Tab and run the setup from there but again failed with some errors. The problem may be the  recovery partition that wasn’t allow windows to upgrade, as windows 8.1 OS rely some files from recovery.

The only option was left is clean install with windows 10 by deleting recovery partition. I read somewhere on web forums that after clean install it will automatically activated but it was not done. For windows 10 upgrade it was the guideline from Microsoft that first run the upgrade over existing OS and it will automatically activated windows when connected with internet. Thereafter clean install can be done. Now after release of new update of windows 10 in Nov’15 (version 1511) it is mentioned on Microsoft site that you can install windows 10 using your Windows 7/8/8.1 keys. But I have not tested it as my all machines are already activated and register with Windows servers.

How to upgrade Acer Iconia W4 820 to windows 10 – Option-1

  1. First backup everything your files, data etc. inside micro sd card or any external HDD
  2. Following files needs to be downloaded from internet, you need a good speed internet connection-
  • Windows 10 Home Single Language 32bit from media creation tool – see the guide
  • Download Acer latest drivers from here , windows 8.1 drivers works without problem as windows 10 drivers still not uploaded
  • Team viewer software from here
  • Download rufus tool for bootable media creation
  • RW everything to extract windows keys from BIOS (run Rw- everything on windows 8.1 system, Click on the ACPI Table button at the top. After that click on the MSDM tab. Your BIOS’s product key is at the bottom, see this post)
  1. You need following tools to upgrade your Tab to windows 10
  • Your Acer Tab – off course
  • Tab Charger
  • USB – OTG Cable
  • A USB hub with minimum three USB ports
  • A USB stick with min 4GB storage
  • A USB Mouse & Keyboard
  • A working good speed wifi internet connection
  1. Charge your tab to fully
  2. From rufus create bootable USB drive, select partition scheme as GPT partition scheme for UEFI, file system as FAT 32, now choose the downloaded ISO image for windows 10 SL  32 bit from image icon. And start button to create bootable drive for your TAB.
  3. Now shut down your Tablet, start by pressing volume up button it will reach to BIOS. Under BIOS inside boot select first boot drive as USB-HDD, second as USB-CD. Exit by saving and restart, again shut down
  4. Now connect usb hub with OTG cable and connect USB mouse and keyboard and also connect USB- drive created earlier in 5.
  5. Restart the tablet by pressing power button; it should stick on Acer logo than seems everything going on right way. After some time 3-5 minutes Microsoft license screen will come, installer will automatically collect the keys from BIOS goes on next step if Windows version is correct as per the earlier pre-installed windows as given on widows 10 site


From Windows 7 editionTo Windows 10 edition
Windows 7 Starter

Windows 7 Home Basic

Windows 7 Home Premium

Windows 10 Home
Windows 7 Professional

Windows 7 Ultimate

Windows 10 Pro


From Windows 8.1 editionTo Windows 10 edition
Windows 8.1

(Also applies to country specific editions, Windows 8.1 Single Language, and Windows 8.1 with Bing)

Windows 8.1 Single Language

Windows 8.1 Single Language with Bing

Windows 10 Home



Windows 10 Home Single Language

Windows 10 Home Single Language

Windows 8.1 Pro

Windows 8.1 Pro for Students

Windows 10 Pro


  1. If installer ask you the keys at the time of installation, it may be possible that you have downloaded wrong version. If it is sure the version is correct e.g. the upgrade version should be Windows 10 Home Single language if coming from windows 8.1 single language/windows 8.1 single language with Bing than you may skip at this time and continue for installation.
  2. On next screen choose custom installation and delete all the partition as shown and on single un-allocated space, click next windows 10 installation will now start to copying files etc. It took long time around 15-20 minutes as data is processing through USB hub and slower as compared to desktop/laptop.
  3. After it is 100%, installer prompted to restart, now remove USB drive otherwise it will again boot into USB drive and go for same loop.
  4. When tab restarted with windows 10, connect it with internet and activate. If not activated automatically, enter the keys earlier extracted using RW-everything and activate windows.
  5. After successful activation copy the Acer driver and Team viewer into the tablet using pen-drive.
  6. Now install first team viewer using mouse and keyboard and take into remote the Tab using some another laptop/mobile. Remove the USB hub, connect the charger and using team viewer run the Acer driver setup as it requested to plug the charger first.
  7. Now you are finished and all apps installed earlier you need to install again

How to upgrade Acer Iconia W4 820 to windows 10 – Option-2

If windows not activated using the above Option-1 as it was done earlier when windows 10 released in July’15. Where windows 10 can only be activated if upgraded over Windows 7 or Windows 8/8.1. You required Windows 8.1 Single Language with Bing to be installed first, but ISO image of the same is not available.

I searched over web over 2-3 days and found that only Spanish version is available on some site but not English version.

Spanish version can be downloaded from these links – – Open This Link directly

You can go directly to link as above as tinyurl also redirected to this link.

For download register on and add the files inside your cloud account. Inside your account you will see this folder- Windows 8.1 with Bing. Open this folder and download the file with name


As this file is only required for windows 8.1 activation do not worry that it is clean or it is in Spanish. This is good thing that you can install windows 10 of any language over this Spanish windows 8.1.

Steps for installing Windows 8.1 with Bing –

Follow the same steps as described above 5 To 11. Use different USB drive of 4GB to save the time and create bootable USB drive using Rufus.

After succesfull installation of windows 8.1 activate is using internet (it will not ask keys during installation and also will activate automatically when connected to internet).

Now insert the usb stick with windows 10 installer and run the installer inside windows 8.1. After completion the installation activate windows 10. Now you can clean install windows 10 if required again as your tablet is registered on Microsoft Servers.

If you have problems on Spanish installer, Google translator help can be taken as it also translate using image by camera.

After windows 10 installation complete, drivers can be installed as described above 13 & 14.

References :