Node-red throw err


When trying to run Node-RED I encountered the following error: Essentially it’s missing the module “express”, as can be seen by the 5 line.

    throw err;
Error: Cannot find module 'express'
    at Function.Module._resolveFilename (module.js:338:15)
    at Function.Module._load (module.js:280:25)
    at Module.require (module.js:364:17)
    at require (module.js:380:17)
    at Object. (/home/alex/Apps/node-red/node-red-0.9.1/red.js:19:15)
    at Module._compile (module.js:456:26)
    at Object.Module._extensions..js (module.js:474:10)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:312:12)
    at Function.Module.runMain (module.js:497:10)


In order to fix it, simply install the missing module using the following command.

npm install express

Note: If you’re getting several of these errors (express, nopt, when, uglify-js, clone, ws, etc) in a row after you’ve download and tried to run Node-RED, you might have missed the step to install all the packages:

npm install --production

Testing Failed: “Failed: error: SBT did not send a reply to our request, perhaps it was killed or failed to start”

Activator error “Failed: error: SBT did not send a reply to our request, perhaps it was killed or failed to start”.

This may be because SBT isn’t installed, SBT is a “simple build tool” for scala which isn’t packaged with the main binaries. You can download and install the latest SBT from the official page, installing it fixed the issue for me in Activator.

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Linux Mint: “Could not download all repository indexes”

When running

sudo apt-get update

or attempting to update via the Update Manager in Linux Mint (13), I was fronted with the following error:

Failed to fetch ... tion-en_US Unable to connect to
Failed to fetch ... slation-en Unable to connect to
Failed to fetch ... tion-en_US Unable to connect to
Failed to fetch ... slation-en Unable to connect to
Failed to fetch ... tion-en_US Unable to connect to
Failed to fetch ... slation-en Unable to connect to
Some index files failed to download. They have been ignored, or old ones used instead.

This is caused by missing repositories which are either old, broken or currently down. In order to fix it, simply run:

sudo apt-get update fix-missing

If this option doesn’t work, try changing the repository mirrors with the following guide.

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To the UWE Robotics Peeps Looking for USB Linux

How to install Ubuntu on USB stick

If you get this problem:

Attempting Boot From USB Device
SYSLINUX 3.63 Debian-2008-07-15 EBIOS Copyright (C) 1994-2008 H. Peter Anvin
Unknown keyword in configuration file.

How to install pyrobot

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Switched RSS Feed to FeedBurner

If you have subscribed to my feed (I have no idea if anyone actually has, and I’m not entirely sure why you would want to but anyway..) I have switched to RSS powered by FeedBurner, it was a really simple process and the reason for doing so is that I like to see which of my posts are well received in order to write better ones in the future. Once the FeedBurner feed has been made it will also give you a guide into replacing all the links to your old RSS feed in order that any new readers will be using it. With page views, traffic sources, returning visitors etc. stats covered by Google Analytics and WordPress have no feedback on who is following your feeds I figured it might be a worth it.

Point of this post being, if you are using my RSS feed it’d be nice if you could change over however the old feed should still get updated so its not a requirement.

Link to new feed:

Link to FeedBurner:

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Is Twitter The Main Force Behind The Wave?

Google Wave has been in and out of the trending topics since the first set of beta invites were available, tons of people are still requesting and sharing invites via twitter many of who would usually not even know about Wave at this point. The massive spread of the service must be astronomical in comparison to Google Mail beta back in 2004 when mass communication tools such as Twitter weren’t around, the closest being Myspace which was only a year old and Facebook, just finding it’s feet. The huge impact Twitter has cause on Google Wave brings me to a few questions..

  • Should software or web apps be put under this much strain this early on in development?
  • It is good that the general public are becoming more aware and involved in beta testing, or should it be left to tech-heads?
  • Where would Google Wave be at without Twitter?
  • What does how openly people are sharing email addresses on Twitter show us about the publics knowledge of internet security?
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Ubuntu – Failed to fetch http://url/filename.deb Could not resolve ‘proxy’

This issue is caused by switching from a proxy to a none-proxy network, even when the proxy has been set to direct internet connection and applied system wide if the system has not rebooted it still seems to be configured to be under that proxy.

The easiest way to fix it is to go to System > Preferences > Network Proxy. Here change to your networks correct proxy setup then click “Apply System-Wide..” you will be prompted to enter your root password twice and then it will be done. If this does not resolve the issue try logging out and back in again or even rebooting your system, this should have fixed it.

The full error I was having is after the break:

$ sudo apt-get install amsn
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
linux-headers-2.6.31-14 linux-headers-2.6.31-14-generic
Use 'apt-get autoremove' to remove them.
The following extra packages will be installed:
amsn-data libsnack2-alsa tcl-tls tcl8.5 tk8.5
Suggested packages:
docker libsnack2-doc tclreadline
The following NEW packages will be installed
amsn amsn-data libsnack2-alsa tcl-tls tcl8.5 tk8.5
0 upgraded, 6 newly installed, 0 to remove and 3 not upgraded.
Need to get 12.5MB of archives.
After this operation, 30.9MB of additional disk space will be used.
Do you want to continue [Y/n]? y
Err karmic/universe amsn-data 0.98.1~debian-0ubuntu1
Could not resolve ‘’
Err karmic/main tcl8.5 8.5.7-1
Could not resolve ‘’
Err karmic/main tk8.5 8.5.7-1
Could not resolve ‘’
Err karmic/universe tcl-tls 1.5.0.dfsg-9
Could not resolve ‘’
Err karmic/universe libsnack2-alsa 2.2.10-dfsg1-8ubuntu1
Could not resolve ‘’
Err karmic/universe amsn 0.98.1~debian-0ubuntu1
Could not resolve ‘’
Failed to fetch Could not resolve ‘’
Failed to fetch Could not resolve ‘’
Failed to fetch Could not resolve ‘’
Failed to fetch Could not resolve ‘’
Failed to fetch Could not resolve ‘’
Failed to fetch Could not resolve ‘’
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

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Howto: Use Xbox Controllers (original, 360, 360 wireless, 360 guitar) with Linux

Great guide by wootah from the of how to get the wireless receiver for PC working under linux, using the Userspace Xbox/Xbox360 USB Gamepad Driver for Linux from grumbel. It works pretty much perfectly, I use it as a remote to control my laptop when it is displayed on my TV.

Supported Controllers

  • Original Xbox controllers through USB (with a cable modification)
  • Xbox 360 USB Controllers
  • Xbox 360 Wireless Controllers through the Wireless USB Adapter
  • Xbox 360 USB Guitar

Some third party controllers may work as well (MadCatz) and they are probably already available. To check support for a particular controller, review the file xboxdrv.cpp and look for the line XPadDevice xpad_devices. You may even be able to add in support for your particular controller by adding the hardware identifiers into xboxdrv.cpp and recompiling the driver (the README talks about this further in depth).


  • Executes in user space on top of libusb. This means that you do not have to recompile the kernel
  • Provides a joystick device (/dev/input/js0)
  • Allows remapping of the buttons and axises
  • Support of the analog triggers (LT, RT) along with reconfiguration into a digital mode (they function just as buttons)
  • Change the LED status of the ring of light on the 360 pads

by ~Wootah – Click here for the rest of the installation.

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My Ubuntu 9.10 Post Installation Guide (64-bit)

sudo apt-get install ubuntu-restricted-extras
Music Applet
sudo apt-get install music-applet
sudo apt-get install banshee
Mirage – Banshee Plugin
sudo apt-get install banshee-extension-mirage
Before Mirage can be used you need to make it scan your music so in Banshee Tools->Mirage Playlist Generator->Rescan the Music Collection as shown below

sudo add-apt-repository ppa:dockbar-main
sudo apt-get update && sudo apt-get install dockbarx

Google Chrome 64bit .deb
Ubuntu 9.10 (x86_64) – Download Page
sudo apt-get install wine
Once Wine has been installed this allows you to use the windows version of Spotify on linux and it work’s pretty well so you can grab that here. Once downloaded if your running Gnome/KDE you should be able to just run the file (just double click it) and it will begin the installation. It’s found under Applications->Wine->Programs.
sudo apt-get install lm-sensors
Two Finger Scrolling
Under the Touchpad tab change the scrolling to Two-finger scrolling.

Gedit Plugins
sudo apt-get install gedit-plugins
sudo apt-get install gtwitter