I've recently had to get Rails and Capistrano up and running on a Windows 8.1 machine. These are the problems I encountered and how I fixed them. All issues were encountered after trying to run an existing Rails 4 project.

My first step was to install Rails using RailsInstaller. This is a great first step for Windows users, as you also get Ruby, Git and DevKit (which is important for building gems that contain native code). I elected to install the Ruby 2.1 version, which at the time of install, was sporting Ruby 2.1.5.

##Invalid Certificate When running bundle, I encountered the following error:

Unable to download data from https://rubygems.org/ - SSL_connect returned=1 errno=0 state=SSLv3

As per the accepted answer on this StackOverflow question, I downloaded cacert.pem and placed it here, C:\RailsInstaller. You also need to tell gem where to find the certificate, which is done by setting a environment variable called SSL_CERT_FILE. This can be done on a temporary basis by typing the following into Command Prompt":

set SSL_CERT_FILE=C:\RailsInstaller\cacert.pem

##Sqlite Native Running any command related to the local Sqlite db, threw up:

cannot load such file -- sqlite3/sqlite3_native

According to this accepted answer, the problem is caused by the version of the sqlite3 gem not supporting Ruby 2.1.3+ on Windows. The gem needed to be updated to at least 1.3.10.

##Bcrypt I encountered a similar problem with the bcrypt gem. I didn't record the nature of the problem, but updating to at least 3.1.7 resolved the issue.

##TZInfo When starting up the Rails server, I received an error relating to TZInfo::DataSourceNotFound. According to the accepted answer on this question, Windows needs an additional gem for the tzinfo gem to work correctly. Add this to your Gemfile:

gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw]

##NPM Error For bonus points, I always install Node along with my Rails installations, if only for JavaScript compilation in Sprockets. Node is best installed using the binary from the official website.

Typing npm into Command Prompt for the first time, returned the following:

Error: ENOENT, stat 'C:\Users\[Username Here]\AppData\Roaming\npm

This issue was resolved by creating the missing npm folder in Roaming. Credit goes to the accepted answer of this question.

##Capistrano On the first day of setup, Capistrano worked like a dream. The following day, after a system restart, no dice. Capistrano tasks kept dying with the following:

Error reading response length from authentication socket

I tried reinstalling certificates and ensured the SSH Agent was running, to no avail. I still don't completely understand the problem, but I think the solution has more to do with the PC's specific environment.

SourceTree was already installed (and running) on the PC, when I came to install Rails. As part of the installation, SourceTree installs Pageant, a Windows based SSH authentication tool.

Basically, Capistrano started working again the moment I had the presence of mind to start Pageant again.

NOTE: The PC has two sets of SSH keys setup, one through Pageant, the other through Msysgit. I thought I'd been using the Msysgit key, but I suspect I was using the Pageant one all along. For Capistrano at least, Git works from the command line, regardless of the status of Pageant.

I'm not aware of any dependancy on Pageant by RailsInstaller. So I wonder whether I wouldn't have this dependancy now, if I didn't already have Pageant on the system. Or possibly, I'd have struggled getting Capistrano working at all, not appreciating the need for Pageant.

##Line Endings I'm still not 100% clear what happened here. We manage a number of GIT repos on Windows & Mac, and have not had this issue before. Upon committing changes to a project, from the Windows machine, all the line endings were converted to CRLF. This caused problems with Rake. My inital attempts to fix the issue on a Mac resulted in me corrupting the Sqlite3 development database, so for the remainder of this fix, assume I've temporarily moved the db (along with all other binary files, i.e. images) out of the directory structure.

From the project root, on a Mac, I ran the following:

find . -type f -not -path "./.git/*" -exec perl -pi -e 's/\r\n|\n|\r/\n/g' {} \;

From Linux, you can run:

find . -type f -not -path "./.git/*" -exec dos2unix {} \;

The above, replaces CRLF with LF for all files in the GIT repo.

After readding the database, I ran rails server to check for obvious issues; all seemed well. As per this Github article, I ran the following on the Windows machine:

git config --global core.autocrlf true

The above, gets GIT to manage line endings on Windows machines, to keep them in sync with GIT's base line ending (LF).