Dual booting Windows 10 and Ubuntu 20.04 - with RST issue fixed 
Tags: ubuntu, beginners, windows10, dualboot
Published: 2020-11-29 11:41:47

_Disclaimer: Steps after taking ISO image can quite vary with respect to the laptop that you use. This blog helps best for the ones using Acer Aspire 7 (i5, 9th gen)_
_Caution: not a very big tech-freak, more of a story-teller_ :grin:

[Fix the _Turn off RST_ right away](#step-5-fixing-the-issue)
__Why Ubuntu/Linux?__
If you are a person who's fed up of downloading millions of stuffs from different sources for a software and still facing errors like something's missing or a person who's lazy enough to move your mouse around, Linux OS would be better for you :smirk:

__Preferable Pre-requisites:__
* 4+ GB RAM
* If Windows 10 is pre-installed, you do not need to worry if Linux can be dual-booted in your system. It surely can. 
* 30+ GB of continuous free space to spare. (Preferably 60+ GB if you are going to use Linux regularly)
* A USB of 4+ GB capacity for storing Ubuntu ISO file for dual booting 

### So, all the best and let's begin
#### Step 0: Back up everything (optional) - _I didn't though_
#### Step 1: Download the [ISO image](https://ubuntu.com/download/desktop) of Ubuntu.

By default it gets downloaded into Software in C:/ though it doesn't matter much where it gets downloaded. 

While you're at it, let's make a bootable USB

####Step 2: Making a bootable/live USB
Even though I used [Universal USB Installer](https://www.pendrivelinux.com/universal-usb-installer-easy-as-1-2-3/) for creating a bootable USB, there are other software too like [Rufus](https://rufus.ie/) and [UNetbootin](https://sourceforge.net/projects/unetbootin/) which might require a download.

Plug in your USB.

In UUI, clicking on the "Download UUI" will bring up a new tab and choose your file location to save it. Go to the location where you have the file and follow:


![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/70kpmyl04nnk4jm2swep.png)

Select your installed Linux Distribution, in this case, Ubuntu
and browse-select its ISO file.
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/9sg5n3vz3js5bagnwziu.png)

![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/bgowhlm2ff4wjzk40nss.png)


Now, choose the USB which is to be made bootable and __format__ it if you wished to. I didn't though, because I had enough space for Ubuntu ISO File too. 
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/b4hbi4342g9hgk0f2lss.png)

Click on ``CREATE`` and you hold a bootable USB in your hand now. 
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/noacwp0hb3kr9s2xbgzs.png)

####Step 3: Shrink and create space for Ubuntu
For that, open __Disk Management__ and right click on <kbd> C: </kbd>
_P.S. : I took this screen print months after dualbooting Ubuntu_
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/2zzf8sn9bfuakqp7gatf.png)
Choose <kbd>Shrink Volume...</kbd>
A window with the image as a part of it pops up. Ideally, type in 20000
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/zei4ndw3kn9063c76us8.png)
As the process gets completed you'll find unallocated space and that's where Ubuntu will live. 


#### Step 4: Boot into Ubuntu and see if there's an issue due to RST in your system.

_Find Boot Sequence Key. For Acer Laptops, it's_ <kbd> F12 </kbd>.

Reboot your system with USB plugged in and continuously press <kbd> F12 </kbd>. Choose Ubuntu and wait till it loads. 
A page like this will be loaded. 
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/7szq1p2dv2jjvtb3l3tv.jpg)

But when you try to ``Install Ubuntu`` you'll get this screen...
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/3opvjmf0c8bj7k6yylek.png)

So, yep... That's the whole reason I'm writing this. Also, I'm just a beginner and not much exposed to the words like `UEFI/Legacy, SATA- AHCI/RAID/IDE` and all. So, until I learn about them, all I can do is type out a solution that worked, __without wiping off the pre-installed Windows 10__ 
Anyway, click on the `restart` option and get back into Windows.

#### Step 5 Fixing the issue
In Windows, open up command prompt as __an administrator__ (`Run as administrator`) and type in ``` bcdedit /set {current} safeboot minimal```

![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/e1uc1sioh5pik1obyejo.png)
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/nyyj81pvyv70ld73hhun.png)

_Find your BIOS setup key. For Acer Laptops it's_ <kbd> F2 </kbd>.
Reboot your system with USB plugged in and continuously press <kbd>F2</kbd>
It should take you to BIOS setup. 
In my laptop, pressing <kbd>Ctrl</kbd> + <kbd>S</kbd> in `Main` tab listed every advanced options.
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/eu6ngp2urfeywi8pfyss.png)
On the `information` page itself new rows get added and search for `SATA mode` and change it to `AHCI` instead of `RAID` (or in rare cases, `IDE`)
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/wlidz8sgx5nxvrxjkf0q.jpeg)
For some of non-Acer laptops, this option is named as `Storage` in `Configuration` tab.

A frightening question will be asked, ```All existing data stored on the drives will be erased when resetting the controller mode. Do you want to proceed? [Yes] [No]```

Don't worry, nothing will happen. Select `YES`
Press <kbd>F10</kbd> and come out of BIOS and you will be automatically taken to ``safe boot mode ``. This just ensures that your Windows is okay to proceed with dual booting.
Open Command Prompt and press enter after typing in ```bcdedit /deletevalue {current} safeboot``` 
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/mq28k2149ug3j4qoxl7n.PNG)

#### Step 6: Setting Sails
Restart the system and now, choose `Ubuntu` from the boot menu (or `Try Ubuntu`, if it exists). 
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/chg2qcnbt3r5naeiia2b.jpeg)
I followed [this site](https://www.linuxtechi.com/ubuntu-20-04-lts-installation-steps-screenshots/) for rest of the steps and VOILA, your Ubuntu is ready to use
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/6f5algcp50k6jbc47h5i.png)
Not gonna lie: A 50+ clicks and tiring setups on Windows while software installation is replaced by just a single line on Terminal Window, `sudo apt install ___`
___Good Luck! Keep Learning___

_Courtesy: My tech-freak dad, loads and loads of websites, YouTube tutorials and two whole days_