Google not loading first time in IE11 via a web proxy on Windows 8.1? Turn off SPDY support.

Update 14/03/14: According to Microsoft, this problem is fixed in the March 2014 Cumulative security update for Internet Explorer. However, I was able to immediately reproduce the problem even after the update was installed, so the below still applies as far as I’m concerned.

As my former boss Bond once said, “If you’re going to live on the cutting edge, you’ve got to expect some blood”. One of the many joys of being an early adopter is finding stupid bugs before everyone else, and so as I began wide-scale testing of Windows 8.1 at my school, we found this one.

In a nutshell, pretty much every time we tried to load www.google.com in Internet Explorer 11, we got a “This page can’t be displayed” message, yet the site would inexplicably load fine just by clicking refresh. We saw the same with other Google sites such as Gmail and Google Drive – but most sites seemed immune. Both the desktop and Modern UI versions of IE were affected.

Like most schools, our web access goes via an HTTP proxy so that content not suitable for the 5 year-old cherubs can be filtered out. We use Smoothwall, which is one of the better filtering products out there, but so many applications are not designed with proxy support in mind that it does occasionally cause problems. It’s very rare for any mainstream browser to have a problem with proxies, but when I bypassed it, the problem immediately went away. What was more curious was that we were already running Internet Explorer 11 on our Windows 7 workstations too, and they didn’t have any problems.

Office 2013 error: “Sorry, we are having some temporary server issues” – fix it by clearing a key in the registry

Update 27/02/14: Microsoft have released Service Pack 1 for Office 2013, and still does not contain a fix for the below issue.

Recently we began using Office 365 accounts with the Office 2013 desktop suite, and during a roll-out session for staff, almost everyone in the room got this error message when trying to load the sign-in screen for their Office 365 account for the first time:

“Sorry, we are having some temporary server issues.”

The error occurred even before asking for any login details, and a quick check of our Internet access logs revealed that Word wasn’t even attempting to contact a server. I hadn’t seen this during testing, and we couldn’t work past the error when we encountered it, so the roll-out session was a bust. To say I was irritated is somewhat of an understatement.

Another way to scan DVB channels: w_scan

This is part of my series of articles on converting digital broadcast TV to IPTV: click here for the other articles in the series.

In previous articles, I’ve given examples of scanning for DVB channels using the scan utility in Linux. However, when I tried doing a channel scan yesterday, it refused to work:

angry-admin@dvb:~$ sudo scan ~/uk-CrystalPalace -u
scanning /home/local-admin/uk-CrystalPalace
using '/dev/dvb/adapter0/frontend0' and '/dev/dvb/adapter0/demux0'
initial transponder 490000000 0 3 9 1 0 0 0
initial transponder 514000000 0 2 9 3 0 0 0
initial transponder 545833330 0 2 9 3 0 0 0
initial transponder 506000000 0 3 9 1 0 0 0
initial transponder 482000000 0 3 9 1 0 0 0
initial transponder 530000000 0 3 9 1 0 0 0
>>> tune to: 490000000:INVERSION_AUTO:BANDWIDTH_8_MHZ:FEC_3_4:FEC_AUTO:QAM_16:TRANSMISSION_MODE_2K:GUARD_INTERVAL_1_32:HIERARCHY_NONE
WARNING: >>> tuning failed!!!

I got a lot more tuning failed!!! messages after that, and no scan results. I’m not sure exactly what is causing this yet, but somebody else in the UK noticed this too, and suspects it began right after a very recent transmitter retune. Luckily, he also had a solution: use a different scanning tool.

Converting your multicast IPTV Freeview to HTTP unicast using udpxy

So, by now you’ve read my previous guides about streaming Freeview/DVB-T channels to your network using VLC and dvblast:

1. The Angry Technician’s Guide to streaming Freeview via VLC, you Idiots
2. How to stream EVERY channel from Freeview onto your network
3. How to stream Freeview HD (DVB-T2) over multicast using dvblast, you Idiots

If you haven’t, you are slacking a bit, as they’ve been up for a while and are the top 3 posts ever on here by pageviews. According to the WordPress.com stats, #2 has been viewed more than 33,000 times, which is frankly a ridiculous number.

Anyway, after all that reading, you might be thinking yo yourself “well, multicast streaming is all nice and fancy, but what I want is some good old-fashioned unicast”. It’s a question that has come up a few times, especially as dvblast will only output multicast streams, so if you want multiple channels per tuner, you are stuck with multicast. There are a few reasons this might not suit your needs, however:

• Not all of your network supports multicast (especially true if you have cheap and nasty edge switches).
• You want to view the streams on clients that don’t have multicast software available (e.g. smartphones).
• You want to access the streams from a different network (e.g. streaming from one location to another over the Internet or a WAN/VPN).

Well, you are in luck. There is another bit of totally free open-source software that will make that conversion for you.

How to fix a ‘User information is disabled’ error on the Canon imageRUNNER Remote UI

This was a pretty weird one, and Google didn’t turn up anything useful, so hopefully this will help anyone with the same problem in future.

Issue

When logging into the Remote UI of a Canon imageRUNNER in System Manager Mode, I got the following message right after entering the System Manager ID and Password, and could not proceed any further:

The problem affected 3 out of 10 of my new printers. All the new printers had replaced existing printers, and I had reused their IP addresses and hostnames. I soon realised that the 3 affected had replaced the 3 Kyocera Mita printers I had, and that all the unaffected printers had replaced different makes.

When I logged in using a different browser, the problem did not occur, so I realised it was something specific to my normal Firefox profile.

Solution

I discovered that the web interface of the previous Kyocera Mita printers had set a cookie named rtl which was the cause of the problem. Removing this cookie for each of the affected printers immediately resolved the problem.

How to stream Freeview HD (DVB-T2) over multicast using dvblast, you Idiots

This is a follow-up to my earlier post, How to stream EVERY channel from Freeview onto your network. If you’re new to this, you’ll want to go and read that one first, or a lot of this article won’t make sense.

Almost a year ago now, the first DVB-T2 USB tuner shipped in the form of the pctv 290e nanoStick T2, and work began on getting it working under Linux. Thanks to the sterling efforts of the developer community, working drivers for this tuner (which is based on the Sony chip) are now shipping as standard with Linux distros that use a kernel version of 3.0 or greater. This includes the recently released Ubuntu 11.10, and since this was my distro of choice for my previous DVB streaming project, I upgraded my streaming server and finally went ahead with buying a nanoStick tuner.

The hardware

At the time of writing, the 290e nanoStick T2 was coming in at just under £80 on Amazon. It comes with a bunch of Windows software I haven’t bothered to look at yet, and few different accessories (including a next to useless sucker-cup portable aerial), but these are the bits from the package you need.

The tuner itself is the size of a fat flash drive, and is about the same weight. That said, you’ll probably still want to use the the included USB flylead to help prevent strain on the USB connector, and you’ll also need the aerial adaptor.

The nanostick only has a small aerial connector, which is what the included aerial uses, but to hook it up to a standard UHF aerial, you use this adaptor.

As expected, Ubuntu detected the tuner immediately and I could tune to a standard definition DVB-T signal straight away using VLC. But we’re not interested in that! We want DVB-T2, for some proper HD goodness. So, lets get started.

How to disable IE9 add-on performance notifications, you Idiots

Within days of an almost painless deployment of Internet Explorer 9 across the site, I began to spot this annoying little git popping up on some of the older machines:

This is a new and well-intentioned feature of IE9 called the Add-on Performance Advisor. Yes, a lot of add-ons are bloated, steaming, piles of manure, which is precisely why I don’t permit my users to install them. Unfortunately, just having Java on many of my older machines is enough to trigger this, and if kids go around disabling that, the next thing that happens is I get a lot of calls from ICT lessons when all the sites they still use that rely on Java don’t work.

Annoyingly, removing the user’s ability to disable add-ons via Group Policy did not suppress the pop-up.

To banish it forever, you need one of the new Group Policy settings for IE9. Specifically, Windows Components\Internet Explorer\Disable add-on performance notifications.

To get these new settings to appear in your Group Policy editor, you’ll need to copy the updated inetres.admx and inetres.adml from a machine with IE9 installed into the appropriate folders in your Group Policy Central Store. Before you ask, there is no standard ADM template, because IE9 isn’t available for Windows XP, you idiots. UPDATE: As a commenter pointed out, ADM templates do actually exist, because some people are still stuck in the dark ages of using Windows 2003 domains.

How to create Exchange Mail Users in bulk using ‘Enable-MailUser’, you idiots

First things first: Mail Users are NOT Mailbox Users. This is a fundamental mixup that inattentive morons seem to frequently fall foul of on Exchange forums. Creating Mailbox Users, being users who have a mailbox in your Exchange organisation, is so easy to do in bulk that it’s even in the Exchange Management Console GUI, so there’s no point in me or anyone else explaining how to do it.

Mail Users, on the other hand, are users that exist in Exchange but have an external address and no mailbox in your organisation. Unlike a Mail Contact, however, this user has an AD account in your forest. Creating these in bulk is a bit trickier and very badly documented. The reason probably stems from the fact that a) the Exchange developers hate anyone without an Exchange mailbox, and b) that the underlying PowerShell commands in Exchange 2007/2010 do not work the same way. And let’s face it, as much as I prefer a GUI for almost any admin task (due to not being a pretentious masochist), the Exchange Management Console is really just a front end for PowerShell.

• Enable-Mailbox is designed to work hand in hand with Get-User, and you can echo the output from the latter directly to the former and bulk create users using a single line of Powershell.
• Enable-MailUser, however, will not take input from Get-User, at least not directly. You also can’t get around this using foreach because of a pipelining issue.

No, a single line of PowerShell to do this is simply out of our reach. For this, we have to resort to… TWO WHOLE LINES of PowerShell:

$enableusers = Get-User -Filter {Department -Like "8*" -And RecipientType -eq "User"}
$enableusers | foreach { Enable-MailUser $_ -externalEmailAddress "$($_.name)@angrytech.com" }

This is the code I used today to automatically add mail users for all my Year 8 students (whose Department field in AD is filled in with their form, i.e. “8B”). There are plenty of other fields you can filter on. The first line retrieves the list of users, deliberately only picking User objects (not MailUser) to avoid trying to add a mail user twice. The result set of this is then enumerated by Enable-MailUser on the second line, specifying that the external email address should be made up of the AD users common name (CN) with @angrytech.com on the end, which is their (fake) email address on Google Apps.

If you already have email addresses filled in on the AD objects, and simply want to reuse this data, the second line would be as follows:

$enableusers | foreach { Enable-MailUser $_ -externalEmailAddress $_.WindowsEmailAddress.toString() }

And that’s how you get around the fact that the Exchange developers were too sodding lazy to have multiple Mail User creation in the EMC.

I still don’t like PowerShell.

Vssadmin is dead, long live Diskshadow

Today while trying to compact a dynamically expanding virtual hard disk in Hyper-V, I ran into a cryptic error message that made bugger all sense:

Error Code: The requested operation could not be completed due to a file system limitation

I tried the same compact operation using diskpart instead, but got the same message, this time with the additional information that I could “See the System Event Log for more information.”

Imagine my surprise when I checked the System event log to find there was nothing about this.

Replicating PHP’s sha1() in VBScript

The reason I wanted to do this will become obvious at a later date, but for now I wanted to get this little script up on its own because I wasn’t able to find a complete solution when I went looking for it.

The following code replicates the basic functionality of the sha1() function in PHP: