Disconnect from an un-mapped "drive" in Windows

In Windows, you can connect to network shares in two ways. You can map a share with any authorized credentials so that this share will appear as a drive letter in Windows Explorer. This way, not only you have a convenient drive letter like Z to work with, but you have the option to have Windows reconnect to the same share after a restart of the computer. This method is recommended if you have a password protected Windows account.

Another way is to go to the share and authenticate every time. This will not create a drive letter for the share. When you log out or restart the computer, this authentication is flushed, necessitating the need to re-authenticate.

There are times when you want to disconnect all connections to all shares for both mapped and un-mapped shares. With mapped shares, it's easy. Simply right click on the share's drive and choose Disconnect. However, with un-mapped shares, there is no apparent icon to act upon. You have to go to the command line and issue the net use command. Of course, logging out and logging back in will also release this share. However, sometimes this is not an option.

By typing net use you will see what un-mapped shares Windows is connected to.

If you want to disconnect these shares, type in

 net use /delete \\server\sharename 

The "server" and "sharename" are different for each network.

The following website has all the info you need.

http://www.howtogeek.com/howto/16196/how-to-disconnect-non-mapped-unc-path-drives-in-windows/

If you want to run a command to disconnect all unmapped drives:

net use * /delete /yes

If you do not want to type, then you can insert this into a batch file. Simply running the batch file will execute the command.

Picking the Right Lock

Computer security is one of my interests and rightly so given that so much of our valuable information is now in electronic form. Moreover, we store more and more of this information not on our personally owned computers but on cloud-accessed computers offered by the likes of Dropbox and its ilk.

With that said, all security measures start with the most fundamental: physical security. It is the security that prevents unauthorized physical access to your valuables. In addition to padlocks and chains, physical security includes doors and windows. When you leave your computer unattended in public or semi-public areas, you would and should lock it down with a security cable anchored to something immovable like a desk. This cable is shackled with a padlock. Unfortunately, the majority of the consumer padlocks out there can be picked by someone with minimal skills and simple handheld tools. These thieves do not even need a bolt cutter to cut the shackles of locks.

An informative Youtube channel called bosnianbill with over 600 videos about locks is worth checking out. I didn't know this is such a fertile field to have over 600 videos about it. You can easily kill a day's worth of time watching these videos, but if you are short on time, the one I recommend to watch is below.

https://www.youtube.com/watch?v=nsJZ_kKjXcE 

This Youtuber has a great dislike of Master locks and makes it clear every chance he gets. Over and over, he shows that he can pick these Master locks within seconds with two simple pieces of tools. Unfortunately, master locks are very popular out there in the US. If you want to secure your valuables and use Master locks, after watching a few of these anti-Master lock videos, I think you will replace them with something else mentioned in the recommended video.

Viewers from around the world would send bosnianbill, challenging him to pick them. Some of the locks are just amazing, attesting to the creativity of the human mind. The weirdest lock is the one seen in the video below:

https://www.youtube.com/watch?v=1ey2SFHbZV8&list=UUp1orOGJwZvjLAvckyxC4Nw

Dropbox Glitch Causes File Deletion

Generally, it is good practice to have more than one backup even if the backup itself is already a second copy of the data. In the case of Dropbox, people use it as the only means of backup found out the hard way recently why this is the case. Dropbox is often used as a means to backup data because it is so convenient due to its transparency. Basically, once it is setup, it creates a folder on your computer called Dropbox. Any files saved into this folder automatically get copied onto the Dropbox server on the Internet. This means there are two copies of the files at all times. If you delete a file, its copy on the server is deleted automatically. When your computer breaks, you can go to another computer and access the same data file on the Dropbox server. If you wish, you can sync these files onto the new computer.

The recent glitch on Dropbox causes data loss. Some files are deleted on both the Dropbox server and because of its sync nature, the mirrored copies are deleted as well. Dropbox normally keeps a copy of deleted files so the user in theory can recover these deleted files. However, the problem is you may not know what files were erroneously deleted so you would not know what to recover on a timely basis before the grace period for recovery expires.

http://www.tomshardware.com/news/dropbox-selective-sync-glitch-cloud-storage-deletion,27872.html

Selective Sync is a Dropbox feature that allows users to select a specific file or folder to be mirrored on the user's local hard drive. For instance, perhaps users take photos on their smartphones, and those images are automatically uploaded to Dropbox. The user may choose not to mirror those images on a local hard drive with limited storage capacity. 

According to Dropbox, the file deletion occurred when the desktop application was shut down or restarted while the user was applying Active Sync settings. The company's email said that the team worked hard to restore those files, indicating that many may not have been rescued from the dark clutches of the trash can.

So what should you do to ensure there is no data loss if you use Dropbox as your only backup? Simple actually. Because you use Dropbox, you already know exactly where the Dropbox data is. It is the Dropbox folder itself. So once in a while, you would simply copy the entire Dropbox folder onto another physical drive. Append to the name of the folder the date of the copying. So the back up folder will have the name of DropboxXX-XX-XXXX where it can be for example, 10-13-14. This will create a folder called Dropbox10-13-14. This way, you will know exactly what is in this backup folder -- all the files stored on Dropbox up until Oct 13, 2014. When the drive that contains these Dropbox folders are full, you can delete the oldest folders based on their names. Easy.

Sabrent WF-RADU Wifi Audio Receiver

Updated on January 31, 2015

Let's say you have a good pair of speakers that uses the typical 3.5mm audio jack, the type that can plug into a computer to play sound from that computer. However, instead of playing from the computer, you want to play from your smartphone to these speakers. While you can do this with an audio cable connecting to the phone, it is cumbersome with the tethering. You want to lose the cable and send the audio to the speakers over the network via wifi. You can do this with a $30 tiny device called Sabrent WF-RADU Wifi Audio Receiver. It supports both the DLNA and Airplay protocol which should make it compatible with almost all smartphones and tablets out there.

The device is small enough to fit comfortably in your palm and lightweight. It has a 4-inch tethered USB cable that is meant to power it and not for data. This means if you plug this into a computer, the computer will not detect it as a device in need for a driver. The computer will only provide it power. There is no battery in the WF-RADU so it has to be tethered to a computer or any 5-volt USB power source during its operation. I used the USB charger that came with the iPhone 5S because the WF-RADU package does not include this adapter.

The WF-RADU also has a female type-A USB port that I am not sure what is used for. I assume it is there so you can use a longer detachable USB cable with both ends of type-A. Incidentally, this kind of USB cable is not part of the USB specification standard which means it is used for specific proprietary purposes. For all the gory details of USB technology and its myriad connectors, I highly recommend you visit this online resource.http://en.wikipedia.org/wiki/USB

The Sabrent comes with a useful sheet explaining its use. If you want additional information, here is its product page. http://www.sabrent.com/category/audio/WF-RADU/

Actually, its product page on Amazon.com has the best info on using this devicehttp://www.amazon.com/Sabrent-Receiver-Supports-Portable-WF-RADU/dp/B00L26YDA4/

As you can see from the Amazon info page, you can use this WF-RADU in either ad-hoc or infrastructure mode. In ad-hoc mode, you do not need a wireless router acting as middleman so you can set this up in cars whose audio system has a 3.5mm audio in jack. This ad-hoc connection can be encrypted with WPA so that unauthorized people cannot easily latch onto this ad-hoc network. However, if you are at home, it's worth your while to set this up in infrastructure mode so that your portable devices can connect to the home network including the Internet while playing to the WF-RADU. If you have a computer such as a laptop that has both wired and wireless connection, you can connect to the WF-RADU with the wireless connection via ad-hoc and to the Internet with the wired connection. This way, you can stream to the WF-RADU and still access the Internet. Or, you can get a wifi adapter so that your computer has two wifi connections: one used for connecting to the WF-RADU while the other to the Internet using wifi.

Below is a screenshot of the product page on Amazon. It basically has all the setup information you need.

    

Physical vs Logical

In computer systems, particularly in networking, there is this concept of physical versus logical. Some people have difficulty understanding the difference. This is a picture I saw the other day at a subway station. It's a diagram of the various lines that run through the tracks. As you can see, there are several train lines that run on the same physical track between the Montgomery and Van Ness stations. Then after station Van Ness, the N line goes off into another direction running on its own dedicated physical track. Likewise, the J line does the same. The remaining lines continue to run on the same track all the way to the West Portal station.

If this were a computer network, the train track is the physical aspect of the network while the various lines are the logical aspect. You can have one physical network cable that carries multiple network signals using various protocols. If this were a computer, then you have one physical computer can can do many things like playing music, accessing the Internet, and so on.

Enable Playback On Other Devices Besides the Built-in Computer Speakers

I support Synology NASes. These are amazing little file servers that are a little more expensive than a typical NAS, but they can do so many things that I still discover new uses for them. I have such a Synology NAS that has a pair of Logitech USB speakers attached to the NAS's USB port. These are puny speakers, but they are on my desk so their sound output is adequate. They get all their power from a single USB2 connector connected to the NAS.

http://www.amazon.com/Logitech-S-0194B-Notebook-Speakers/dp/B005FXOEYK

Using a web-browser, I would log into the Audio Station at http://192.168.1.11:5000/audio/. (Your Synology may have a different IP address). I log in as a non-admin account that has Read permission to the Music share and use permission to the Audio Station service. While under this user, music files can play to the headphone or speakers attached to the computer, there is no option to play to the Logitec speakers attached to the Synology itself. This is annoying because I have to leave the computer on to play music. I only want is the music to be played from the Synology and the USB speakers. This way, I can turn off the computer and still can listen to the music.

It turns out by default, a non-admin user on the Synology cannot play to physically attached USB speakers or to another DLNA or Airplay playback device on the same network such as a network speaker. Incidentally, Synology supports both DLNA and Airplay.

The solution is to log into the Synology DSM as the admin. Click on the Main Menu at the top. Select Audio Station. Click on Settings. Click on Privileges. Check the box where it says USB/DLNA Render for the non admin user you want to use the USB speakers attached to the Disk Station.

Now when you log in as this non-admin user, you will see additional options for playback devices from the Audio Station. This includes when using the DS Audio app on the iPhone.

A search for DLNA and Airplay speakers on Amazon shows dozens of such speakers. In theory, any of these speakers can be used as the target for the Audio Station. If you have a favorite non-network speaker, you can buy this device to enable DLNA and Airplay for it.

Sabrent Wifi Audio Receiver
http://www.amazon.com/Sabrent-Receiver-Supports-Portable-WF-RADU/dp/B00L26YDA4/ref=sr_1_2?ie=UTF8&qid=1412569527&sr=8-2&keywords=dlna+speakers