R and RStudio Setup Guide — BA 3316
Read your platform's (macOS or Windows) steps all the way through once before you start. Then work the five parts in order — no computer experience needed.
Before you start
Set aside about 20 minutes. You will need your Mac password. Install R first, then RStudio — RStudio looks for R when it opens, so in the other order it won't work.
Macs come with two kinds of processor, and R comes in two matching versions. Download the wrong one and R either won't install or will run badly. Both checks happen in the same window.
If the window says
Chip: Apple M1
(or M2, M3, M4 — plus any Pro, Max, or Ultra)
In Part 2 you download the file ending in -arm64.pkg
If the window says
Processor: Intel Core i5
(or i3, i7, i9, Xeon)
In Part 2 you download the file ending in -x86_64.pkg
If the window is confusing
See the word Apple next to a letter-and-number like M1 or M3? You're Apple Silicon. See the word Intel anywhere? You're Intel. Macs sold from late 2020 onward are almost all Apple Silicon.
Above the chip line you'll see macOS followed by a name and number — for example macOS Sequoia 15.5.
Write down your chip, then close the window with the red dot in its top-left corner.
R is the engine that does the computing. You'll almost never open it directly — but it has to be on the machine before RStudio will work.
R-4.6.1-arm64.pkg
Listed as “For Apple silicon (M1,2,..) Macs”.
R-4.6.1-x86_64.pkg
Listed as “For older Intel Macs”.
Ignore everything else on that page. You do not need the tools, the sources, XQuartz, or anything labelled “development”, “patched”, or “next”.
If a box asks for access to your Downloads folder, click OK
Partway through, macOS may ask whether the Installer can access files in your Downloads folder. Say yes. If you click “Don't Allow”, this install fails and you won't be able to install anything else from Downloads afterward — you'd have to move the file somewhere else to recover. This prompt is normal and expected.
You don't drag R anywhere
R arrives as an installer — a .pkg file — which puts R into your Applications folder for you. That's what the password was for. The dragging step is coming in Part 3, and it's for RStudio only.
Confirm it worked: in Finder, click Applications in the sidebar. You should see a folder called R with an app called R inside it. Leave it alone — RStudio uses it behind the scenes.
RStudio is the program you'll actually use every day. One download works on both chips — the Apple-versus-Intel choice only mattered for R.
.dmg and is named something like RStudio-2026.08.2-200.dmg..dmg file.The window you just dragged from is not a folder on your computer. It's a temporary disk image — think of it as a CD your Mac pretended to insert. If you open RStudio by double-clicking the icon in that window, you're running the program off the pretend CD instead of off your computer. It looks fine, until you restart your Mac or the image gets ejected. Then RStudio vanishes, your settings are gone, and you're stuck mid-assignment.
Dragging it to Applications is what actually installs it. Ejecting is what proves you did.
.dmg file to the Trash. You won't need it again.Today is the only day you'll launch RStudio from the Applications folder. After the project walkthrough, you'll open it a different way every single time.
During the project-guide walkthrough you'll build your course folders and create a file called Project.Rproj inside the Project folder. That file is your front door from then on: double-click Project.Rproj and it opens RStudio and tells it which folder you're working in.
That second half is the part that matters. Launching RStudio on its own leaves it pointing at some arbitrary folder, so your scripts go looking for data/ and out/ and can't find them — you get file-not-found errors even though your code is perfectly correct. Opening the project first makes those paths work.
So the rule is
Today: Applications → RStudio, once, to confirm it installed. Every day after: double-click Project.Rproj. You'll rarely need the Applications folder again.
Thirty seconds now saves an afternoon later. This proves the download in Part 2 matched the chip in Part 1.
R prints one line straight back. Match it against your branch:
"aarch64-apple-darwin20"
Anything containing aarch64 or arm64. Correct if Part 1 said Apple.
"x86_64-apple-darwin20"
Anything containing x86_64. Correct if Part 1 said Intel.
If it doesn't match
Go back to Part 2, download the other file, and install it right over the top. Nothing breaks — the new install simply replaces the old one. Then quit RStudio completely (RStudio → Quit RStudio) and open it again.
Almost every Mac setup problem is one of these. Click a line to open it.
R is either missing or was installed after RStudio. Do Part 2, then quit RStudio completely and open it again.
You downloaded the wrong chip version. Go back to Part 1, recheck, and get the other file in Part 2.
Usually an Apple Silicon Mac running the Intel version of R. Run the check in Part 5.
The download was interrupted. Delete RStudio from Applications, download the .dmg again, and redo Part 3.
The current versions need macOS 14 (Sonoma) or newer. You have two options: update macOS if your Mac supports it (Apple menu → System Settings → General → Software Update), or install older, compatible versions of R and RStudio. Come to office hours for the second option — don't guess at which older version to grab.
Move the .pkg file out of Downloads — drag it to your home folder or the Desktop — and double-click it there. To fix it properly: System Settings → Privacy & Security → Files and Folders, find Installer, and turn Downloads back on.
Open Finder, then use the menu bar at the very top of the screen: Go → Applications.
Still stuck
Bring your laptop to office hours. Don't spend more than 30 minutes fighting this alone — that's what office hours are for.
Before you start
Set aside about 20 minutes. Install R first, then RStudio — RStudio looks for R when it opens, so in the other order it won't work.
Good news for PC users
There is only one R download for Windows. Unlike Mac users, you do not have to work out which processor you have. What you do need to check is your Windows version — that's Part 1.
The current RStudio requires Windows 11. If you're on Windows 10, find that out now rather than three screens into an installer.
about and press Enter. A settings page called About opens.If Edition says
Windows 11 Home
(or Pro, or Education)
Continue to Part 2. Nothing else to check.
If Edition says
Windows 10
(any edition)
Stop here. See “I'm on Windows 10” at the bottom of this page.
While you're on that screen
A little higher up, under Device specifications, the line System type should read 64-bit operating system. Essentially every machine sold in the last decade does. If yours says 32-bit, come to office hours — R no longer ships a 32-bit build. And if that line ends in “ARM-based processor” rather than the usual “x64-based processor” — you have one of the newer Snapdragon laptops — stop here and come to office hours before you install anything.
R is the engine that does the computing. You'll almost never open it directly — but it has to be on the machine before RStudio will work.
R-4.6.1-win.exe.Nothing to drag on Windows
Mac users have to drag RStudio into a folder by hand. On Windows, both installers put the programs in the right place for you. Your job is just to click Next and accept the defaults.
Confirm it worked: click Start and type R. You should see an app called R x64 4.6.1 in the results. Don't open it — RStudio uses it behind the scenes. You just need to see that it exists.
RStudio is the program you'll actually use every day. One download works on every Windows PC — there's no version choice to make.
RStudio-2026.08.2-200.exe.Windows may show “Windows protected your PC” with only a Don't run button visible. This does not mean the file is unsafe — it means Windows hasn't seen this particular file often enough yet. It appears for almost every newly released installer.
Click the small More info link inside the blue box. A new button appears: Run anyway. Click it.
.exe files. You won't need them again.On a school or work laptop
If the “allow this app to make changes” box asks for an administrator username and password that you don't have, email me — your laptop is most likely being managed by an administrator or organization.
Today is the only day you'll launch RStudio from the Start menu. After the project walkthrough, you'll open it a different way every single time.
RStudio.During the project-guide walkthrough you'll build your course folders and create a file called Project.Rproj inside the Project folder. That file is your front door from then on: double-click Project.Rproj and it opens RStudio and tells it which folder you're working in.
That second half is the part that matters. Launching RStudio on its own leaves it pointing at some arbitrary folder, so your scripts go looking for data\ and out\ and can't find them — you get file-not-found errors even though your code is perfectly correct. Opening the project first makes those paths work.
So the rule is
Today: Start menu → RStudio, once, to confirm it installed. Every day after: double-click Project.Rproj.
One thing never to do
Don't go back to Downloads and double-click RStudio-2026.08.2-200.exe to start the program. That re-runs the installer, not RStudio — which is why some students end up installing it four times. Deleting those files (Part 3, step 7) removes the temptation.
Thirty seconds now saves an afternoon later.
R prints one line straight back:
"x86_64-w64-mingw32"
This is what every Windows install should say. You're done — go on to the course folder setup.
an error, or
no response at all
Check the troubleshooting list below, then bring it to office hours.
Worth a second check
Type R.version.string and press Enter. It should report version 4.6.1 or newer. An older number means Windows found a leftover R from a previous install — email me to see if it needs to be updated.
Almost every Windows setup problem is one of these. Click a line to open it.
Expected, and not a sign of a bad file. Click the small More info link inside the blue box, then click Run anyway.
R is either missing or was installed after RStudio. Do Part 2, then close RStudio completely and open it again from the Start menu.
Current RStudio requires Windows 11. Update if your PC is eligible (Start → Settings → Windows Update). If it isn't eligible, you'll need an older RStudio release that still supports Windows 10 — come to office hours rather than guessing at which one, since it has to be paired with a compatible R.
Email me — your laptop is most likely being managed by an administrator or organization.
Go ahead and install it. Go to cran.r-project.org/bin/windows/Rtools, download the version that matches your R (4.6), and run the installer accepting every default. Then close RStudio and open it again.
OneDrive syncs files in and out from under R while it's working, which produces errors that look like your code is broken when it isn't. Keep your course folder somewhere outside OneDrive — for example directly under C:\Users\yourname\. If your Documents folder is already synced to OneDrive, don't put the course folder there.
Harmless — each install replaced the last. Delete the .exe files from Downloads and always open RStudio from the Start menu instead.
Still stuck
Bring your laptop to office hours. Don't spend more than 30 minutes fighting this alone — that's what office hours are for.