Using CHNTPW to fix weird bug in Windows 7

I just spent a good many hours trying to fix a Windows 7 machine with a ‘broken’ login.  The user hadn’t changed their password (nor had it expired) but suddenly the computer insisted their password was wrong.  My first thought was just to reset (hack) the password.

I had previously used the ‘chntpw’ tool to manually tweak the built-in SAM password database on Windows XP – but did it work on Windows 7, too? I carry a flash-drive on my key-chain which boots Ubuntu 10.10 so I started there.  ‘Chntpw’ is in the 10.10 repository (the ‘Universe’ alternate) and I successfully installed it, then ran it against the Win7 machine’s hard-drive and SAM file. It said it had 'successfully' blanked the user’s password but Windows still reported ‘invalid password’. I also tried resetting to a new password; same result.

I then tried one of the official Windows 7 repair techniques. I booted the install disc, then selected Repair > Recovery Console. Once I had the command-line open I tried the following command which was supposed to activate the built-in Administrator account,

> net user administrator /active:yes

Unfortunately, even though this was using a ‘legit’ Microsoft process it still didn’t work; there was no Administrator login option.

At this point, I thought maybe there was a newer version of ‘chntpw’ so I booted a newer Ubuntu 11.04 LiveCD. But there was no version of ‘chntpw’ in its Universe repository. Instead I had to download the .deb from Launchpad (just google “ubuntu 11.04 chntpw”). Unfortunately, attempts to both blank and also reset the user password still failed.

Finally, I tried unlocking the Administrator account with chntpw and it finally worked! I still couldn’t login as the regular user-account but I was able to click on Switch User > Other User > manually enter ‘administrator’ (sans password) and it logged me in.
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Now, here's the weird bug part:

From the administator login I was able to successfully reset the user's password and login as them.  I immediately saw a weird error message, something about "user profile directory c:\windows\system32\config\Desktop not found."  The user's Desktop folder is not supposed to be under C:\Windows?!  Also, the system loaded a generic desktop.  I switched back to the Administrator login and searched the C:\Users folder.  The user's original Desktop folder was right where it was supposed to be, and I noticed something unusual:  There was a copy of the files off a Norton Antivirus install CD filling the Desktop.  I also saw the AUTORUN.INF and, on a suspicion, I deleted it.  Voila!  The user's account now worked properly.

So, apparently there is an unpatched Microsoft bug wherein Windows will try to 'obey' an AUTORUN file in the user-profile directory.

Unacknowledged problems with Intel SATA?

For a long time I've had to deal with ongoing 'flakiness' problems with the hard-drives in our Dell laptops. Recently, it got so bad that I decided I had to do something about it! The only clue I had was the large number of 'device timeout' errors in the Windows XP Event Viewer. I had previously been told (by multiple co-workers) that the messages were false/cosmetic. They were easy to check for by applying a filter to the System event-log for either source= 'atapi' or source= 'iastor'.

DRIVER UPDATE 'FIXES' ERROR, SOMETIMES

The first thing I figured-out was that some of the errors were cosmetic but only on our newer E-series laptops (the E6400 and E6410). They had always ever been setup with the older/generic version of the Intel SATA driver, 'iastor' v8.8. Once I upgraded these machines to the newer v9.6 the errors went away.

I also figured-out a relatively reliable way of testing for the error. Without explicitly testing for it, I was seeing the 'timeout' errors every 1-4 weeks under normal usage. If I left a machine logged-in and running overnight, however, it almost always reported new errors in the middle of the night.

PROOF OF LEGITIMATE HARDWARE PROBLEM

Most importantly, I was able to now demonstrate that these errors were NOT cosmetic on any of our Latitude D630 laptops. I spent about a MONTH swapping HDs between different machines, reimaging them, using the latest Intel SATA driver versus the older/default, even re-installing in AHCI vs ATA mode. The results were conclusive: the timeout errors were from the motherboard. And, the problem only occurred on the machines I had purchased between January 2008 and October 2008, i.e., it really seemed to indicate a bad batch.

Unfortunately, by this point, most of my D630s were out-of-warranty; most by just a few months. Dell was willing to replace the motherboards on all the in-warranty machines, of course, but I had a real argument with them about the rest. I pointed out how the problem seemed to be a manufacturing defect and that it had taken me a LONG time to prove.  They ended-up granting me an additional 60 day 'grace' period on the warranties. So 7 of the 13 affected laptops are going to be repaired.
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CONSPIRACY THEORY

All of this got me thinking: Why do any of these machines show a SATA 'timeout' at all? I heard that the latest 'Sandy Bridge' chipset had been recalled because of an obvious defect in the SATA-2 controller. But is there a larger problem with Intel's chipsets? Why does the error occur on E-series laptops if you use an older revision of the Intel driver? Is it really a cosmetic error, or is it a universal problem which the newer version of the driver simply ignores?
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Comparing old JVC KW-XR810 to new KW-HDR720

I have the JVC KW-XR810 double-DIN receiver in my car and love it.  But it still has it's limitations.  Most of all I miss having more EQ frequencies to play with, plus I'd like to have HD Radio.  (Though I suspect HD Radio is slowly dying.)

Now JVC has introduced a new KW-HDR720 receiver which is the 'mid-range' model in their line-up of double-DIN radios.  Both units are very similar and JVC has not made it easy to compare the detailed features of both units.  So I have painstakingly reviewed both User Manuals and present my findings below.

older XR810 ($300 at Crutchfield)

• includes Bluetooth adapter
• supports HD Radio but not included
• parametric EQ has 3 bands each with 3 frequency settings
• subwoofer level can only be adjusted by digging through Menu settings
• supports Sirius satellite radio
• supports Bluetooth profiles: HFP 1.5, OPP 1.1, PBAP 1.0, A2DP 1.2, AVRCP 1.3
• separate High-Pass and Low-Pass crossovers for mains vs subwoofer
• dedicated 'Phone' button
• 'full-dot' LCD

newer KDR720 ($220 at Crutchfield)

• supports Bluetooth adapter but not included
• includes HD Radio
• parametric EQ has 3 bands each with 4 frequency settings
• subwoofer level adjustable directly from EQ window
• no support for Sirius satellite radio
• User Manual has no details about Bluetooth profiles
• no separate High-Pass crossover for mains; just 'on/off' ?
• dedicated 'Tag' button for HD Radio which doubles as 'Phone' when used with bluetooth
• old-style 'segmented' LCD lettering

 They also have the 'low-end' KW-XR610 model which is the same as the XR-810 minus the $100 USB bluetooth adapter; the KDR720 uses a different adapter.

I'm happy to see the additional EQ frequencies but wish they'd included even more.  Also, I'd like to know if the bluetooth support has been improved.  My current setup (XR810 paired with HTC Hero running Android 2.3.3) has inconsistent phonebook support and also is missing any audio display functionality (which I think requires AVRCP 1.4).
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UPDATE: Ha!  No sooner had I written-up all this then I noticed the following PDF on the JVC product web-page. It shows that the KDR720 has the same level of bluetooth audio support (as the XR810) but not the phonebook support.  It also looks to have superior radio-tuner performance, in general (not just with HD).
Comparison Chart of JVC Car Audio receivers
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Is Sprint coverage getting worse?

In the past month I've noticed that I lose 3G data service in lots of places, and more importantly in places where I used to have plenty of coverage.  I decided to google "is sprint coverage getting worse" and learned that I am not alone.  In the past couple of months there have been lots of similar discussion threads, e.g.
howardforums.com/showthread.php/1717175-Just-me-or-is-4G-coverage-getting-worse
sprintusers.com/forum/showthread.php?t=218830

The really significant one seems to be this detailed post on the Sprint Community forum,
community.sprint.com/baw/thread/66975

My initial suspicion had been that Sprint was preparing to announce their "new 4G service" here in San Diego, and that they were re-purposing existing 3G towers for the effort.  Now I'm not so sure.  Even in areas with existing 4G service, the coverage map has dramatically shrunk recently.  The discussion on Sprint Community is too long for me to read right now but the gist seems to be that Sprint never really had full 3G coverage -- instead they were paying for 'seamless' roaming on other networks (cough*Verizon*cough) and now they're not.

I was already thinking of switching to T-Mobile for their better selection of Android phones and existing '4G' coverage.  This is now yet another reason to do so.
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Considering NAS and DLNA servers

SWITCH TO NAS BASED FILE-SHARES?
My current network consists of a 24/7 Ubuntu workstation (with a dual 1 TB RAID) and Win7 HTPC (also with dual 1 TB).  I am also seeding a bunch of torrents (mostly Ubuntu distros) and hosting the Squeezebox server for the Logitech Radio in our kitchen.

I am considering scrapping the Ubuntu workstation and reinstalling it with Win7 and an SSD.  I would like to save on our electricity bill and improve the file-sharing and backup.  So I am investigating Network Attached Storage (NAS) options.  So far the Netgear ReadyNAS seems like the best option as it's a Linux-based OS with add-ons for all the major services.  Right off the bat it has Tivo and DLNA support, and there are also plug-ins for the Transmission bittorrent app as well as for the Squeezebox server.  The ReadyNAS Ultra 2 has a single-core Intel Atom while the Ultra 2 Plus has dual-core.

The one thing the ReadyNAS wouldn't be able to do is host my new weather station (really just a Oregon Scientific RMS300A three-source temperature and humidity monitor).
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SWITCH TO DLNA BASED VIDEO-STREAMING?
I am also debating the usefulness of DLNA.  One of my friends has a new Samsung plasma HDTV with DLNA support and such a thing should -- in theory -- negate the need for an HTPC (and XBMC).  The problem seems to be the limited codec and encoding support in DLNA.  I assume this was on purpose, to prevent people from downloading ripped content and directly playing it on DLNA players.

Fortunately there's a workaround -- a DLNA server with transcoding!  Windows 7 includes Windows Media Center which already includes a DLNA server, but unless the original files are already in DLNA-compatible formats you won't be able to play them on something like the Samsung TV.  I also already own the Nero 9 Suite which includes the Nero Home DLNA server, but again I don't think that includes transcoding.

Instead, I have found the following two options for DLNA transcoding:

Mezzmo, $30
www.conceiva.com

iSedora, $17 (single-device) / $48 (multi-device)
www.isedora.com

At this point the whole investigation is moot since I'm not about to scrap my primary workstation!  Since it's running Ubuntu 10.10, though, it'll eventually lose support/updates and that will certainly force my hand.
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How to make ATI 785G (4200) pass DD and DTS through HDMI

I just replaced my WinXP-based HTPC with a new Windows 7 Premium system. The new PC has an ATI 785G motherboard with the 4200 IGP video card. I have the HDMI output connected to my Denon receiver and everything seemed to be working ok.

When I tried playing a movie in XBMC, however, all I could get was stereo. I went into the System > System > Audio settings and set Output=HDMI and enabled both 'Dolby Digital capable' and 'DTS capable'. But then the movie went silent and stuttered badly. I tried the same test with Media Player Classic - Homecinema and got the same result. What did I have to do to get surround-sound?!

After much research I finally determined the following:

1. The ATI 785G chipset supports DD and DTS passthrough on HDMI but not with the standard ATI drivers! (It does not ever, however, support HD audio-passthrough, e.g. from Bluray)
   
2. The standard ATI drivers create both an "ATI HDMI" audio device and a virtual Realtek SPDIF device. Deleting the latter doesn't help, nor is it recreated.
3. The audio chip on the motherboard is from Realtek and they provide their own alternate (better!) driver, www.realtek.com.tw/downloads
4. You can download the improved driver at their web-site under High Definition > ATI HDMI Audio Device

Once I installed this alternate driver I was able to go into the Control Panel > Hardware and Sound > Manage Audio Devices > Realtek HDMI > Properties. Under the 'Custom' tab there's a new option for "Allow AC3/DTS/WMA output (Reboot required)". Enabling this, then rebooting, finally fixed the problem!
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UPDATE 9/14/11 - I started having problems where the audio-link wouldn't sync-up (i.e., no sound) even though the Windows volume-control said it was working.  So I uninstalled the Realtek HDMI driver, then updated to the latest ATI Catalyst 11.08 driver.  Everything seems to be working now, and without the 'unofficial' fix!

New recommendation re printers for Ubuntu

I just heard that the forthcoming Ubuntu 11.04 will included automatic support for Epson printers! This is very exciting. Epson now joins HP and Brother in having good Linux/Ubuntu support. I have had too many problems with HP, however, to ever recommend their scanners or inkjets to people. I currently have a Brother fax/laser setup and it's working fine, if slow. (Not sure if there's a software problem or not, i.e., it might be trying to print at an overly-high resolution?)

As for recommending Ubuntu itself, I'm still on the fence. I continue to love Ubuntu and prefer it over Windows 7 for my personal work. But I continue to have weird hardware compatibility problems which come-and-go with different kernel updates, and my sound and fast-user-switch continue to fail. So I'm no longer so enthusiastic in my Ubuntu recommendations.

I've also been using Windows 7 a lot and haven't had any problems with it. Which is good, since you have to pay for it!
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