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Simple erasure of a disk (or thumb drive). Windows 7 “full” format will overwrite each byte on the disk with zeroes.  This began with the Vista o/s and is true also with Windows 7.  This can cause problems for virtual machines running on a SAN.  Here is the statement from Microsoft KB 941961: [more]
 
The format command behavior has changed in Windows Vista. By default in Windows Vista, the format command writes zeros to the whole disk when a full format is performed. In Windows XP and in earlier versions of the Windows operating system, the format command does not write zeros to the whole disk when a full format is performed.

The new format behavior may cause problems for the on-demand allocation modes that a volume storage provider, such as a Storage Area Network (SAN), supports. Problems may occur because the new format behavior prematurely triggers allocation of the backing space.

In the on-demand scenario, zeros do not have to be written to the whole disk because the volume storage provider initializes the on-demand-allocated data. To avoid causing unnecessary on-demand-allocation, you must use the quick format option.

Typically, we run memory diagnostics from a bootable CD, but if you are trying to troubleshoot a computer in another city this is not always possible. Windows 7, Vista, Server 2008, and Server 2008 R2 have a built in utility called mdsched.exe. The utility can be started from a Windows session and will start automatically at the next reboot. The default is a simple memory diagnostic, but extended testing can be performed. Results will display during the test, on screen after the test, and in the Event Viewer under Applications and Services > Microsoft > Windows > MemoryDiagnostics-Results > Memory Diagnostic Tool  after the test is complete.
More detailed information can be found here: [more]

http://www.sevenforums.com/tutorials/715-memory-diagnostics-tool.html

Over the years, many people have asked me about backup for home machines.  Burning files to DVDs and carry them to a different location is problematic.  It's a lot of trouble to make frequent offsite backups.  I recently did some research and decided on using a program called Duplicati for backup and Amazon S3 (Simple Storage Service) for storage.  I think having the backup program and the storage separate is the best solution.  I can even back up to multiple providers in case one of them just goes away without warning.

Duplicati is free and open source and runs on Windows, Linux and MacOS.  It has a nice GUI interface plus a rich command line.  Duplicati has built-in AES-256 encryption, which means you hold the key and your backups are encrypted before leaving your network.  It creates normal zip files and then encrypts them with AES Crypt, so even if Duplicati breaks, you can still download, decrypt, and unzip your backups using other standard tools. [more]

Duplicati will back up to many different cloud providers (Amazon S3, Rackspace, Google Docs, SkyDrive, Tahoe-LAFS, WEBDAV, FTP, SSH) as well as file based locations.

I chose Amazon S3 for storage because of the history of reliability of Amazon.  The cost if not much either.  You get 5 GB free, and then it’s 12.5¢/GB/month after that.  So you can store 50GB for less than $6/month.  It is even cheaper if you choose the Reduced Redundancy Storage (RRS).

Get Duplicati here http://www.duplicati.com/.

Sign up for Amazon S3 storage here http://aws.amazon.com/.

While installing a wireless network at a youth camp where I volunteer,  I was having issues getting the wireless distribution system to see the wireless access point in the building where the main router is located. If I place the WAP in the attic I could get a decent signal. So I moved the WAP to the end of the building, in the attic and mounted it inside the wood eave of the building. I was then getting a good signal to my other building. It wasn’t till after I had done this that I realized it never would of worked the first way I was trying. Most of the older buildings, such as the one the network originates from, have stucco exteriors. Part of the process of installing stucco (at least the old way) is to wrap the building in a wire mesh to help hold the stucco. It finally occurred to me that the wire mesh was creating a faraday cage around the building preventing the wireless signal from reaching outside.

I’ve been working on migrating an Exchange environment to 2010. This process includes an upgrade to the Unified Messaging role of Exchange to 2010 as well. We had purchased a UCC certificate to include all the Subject Alternate Names our Exchange environment would need and I had already applied it to the CAS server successfully. Since this certificate also included the FQDN of our UM server, I added the cert. and assigned the UM service to it so that Exchange could start processing voicemails through 2010 instead of 2007. [more]

After I had moved a couple of mailboxes (including mine) over for testing, I discovered that I could no longer receive voicemail. People were redirected to the Subscriber Attendant instead of my individual mailbox. There were events logged on the UM server saying the following:

Event ID: 1400 Source: MSExchange Unified Messaging
The following UM IP gateways did not respond as expected to a SIP OPTIONS request. Transport = TLS, Address = lync.ourdomain.com, Port = 5061, Response Code = 0, Message = This operation has timed out.

After considerable troubleshooting, I ran across a forum posting (http://social.msdn.microsoft.com/Forums/en-US/communicationsserversdk/thread/2733adf2-c91b-4b94-bf43-be93cdd2d5ef/) from someone who encountered the same issue and called for a support incident with Microsoft to figure out what was going on. In order for UM to work in a Lync phone system environment, the Subject Name of the certificate installed must be the FQDN of the UM server itself. It won’t work if it’s just included as a Subject Alternate Name; it must be the Subject Name.

I generated a new certificate from our internal CA with the UM server as the SN of the certificate, installed and assigned it to the UM roles (leaving our UCC cert running the remaining roles), and immediately started receiving voicemail notifications.

I found one other blog posting after the fact that backed this claim up even more (http://therealshrimp.blogspot.com/2012/03/multiple-exchange-um-servers-and.html).

Citrix XenApp has a feature called Client-to-Server content redirection. If content redirection is used, when a user double-clicks a file the corresponding application is started on the Citrix server. For example, a user clicks a document with a .xlsx extension from their PC and Excel is started on the Citrix Server. Content Redirection is set per published application through the Citrix Management Console. By default, most widely used applications (MS, Adobe) will add all known possible extensions to the registry during installation. Citrix pulls these registry settings (extensions and associated filetypes as shown above) from the HKLM portion of the registry. There is not a way to add extensions manually within the Citrix Management Console. [more]

Certain applications do not add all the necessary registry entries for all extensions that may be used by the application. With Windows 2008, there isn’t a way to add extensions via windows explorer as there was in Windows 2003. Users can add extensions by using the open with command and choosing a program to associate with the unknown extension. However, this adds the association to the HKCU portion of the registry which will not be read by the Citrix Management Console when extensions are imported. You can use the following steps to solve this problem:

1. Using the following commands from the command prompt to set file associations globally on a server:
   • To display a list of file extensions and their associations, type assoc at a command prompt, and then press ENTER.
   • To display the association for a specific file extension, type assoc .<xxx> at a command prompt, and then press ENTER, where <xxx> is the file extension whose association you want to view.
   • To change the association for a specific file extension, type assoc .<xxx>=<file type> at a command prompt, and then press ENTER, where <xxx> is the file extension whose association you want to change, and <file type> is the program, dynamic data exchange (DDE), or OLE object you want to associate with the file extension.
   • To display the open command to use when launching a certain file type, type ftype <file type>  at a command prompt, and the press ENTER, where <file type> is the program, dynamic data exchange (DDE), or OLE object you want to associate with the file extension.
   • To change the program association for a specific file type, type ftype <file type>=<program path> at a command prompt, and the press ENTER, where <file type> is the program, dynamic data exchange (DDE), or OLE object you want to associate with the file extension and <program path> is the path to the executable used to open the application.
   • If the file type for the extension you are wanting to add already exists (for example Excel.Sheet.12), all you would have to do is associate the new extension with that file type. This would allow the new extension to open with the program associated with that file type.
     
   • If the file type for the extension you are wanting to add does not exist or you do not know what its file type is, you would have to add both the association and the file type. The example below associates the extension .tstx with the file type test.document. It the associates the file type test.document to open with the program test.exe. This would allow any documents with the extension .tstx to open with test.exe.
     
2. Once the association has been added to the registry, complete the following steps in the Citrix Management Console to view the new file associations:
   • Within the console, browse to Citrix server from which you are running the console (this should be the same server on which you added the file extensions)
   • Right click server, select Other Tasks > Update file types from registry.
   • Browse to published application with which new association should use content redirection with.
   • Right click application and choose application properties and select content redirection menu.
   • Uncheck “show all available file types for this application” (if necessary), click apply, and then recheck the option. This should refresh the file extensions added to the registry in previous steps.

I was working on an SBS 2003 server that had e-mails for one user that would not deliver.  They were stuck in the Local Delivery Queue in Exchange 2003 in a retry state.  I tried to force connection, but they would never budge. 

I turned on diagnostic logging to get more information about what was going on in the Event Logs.  What I saw was “EcLocallyDiliverMsg to the store failed.  Error code: -1605, Event ID 327”. 

Some investigating seemed to point to a problem with the user’s mailbox, and that we would need to rebuild the user’s mailbox.  I exported all of the user’s mail to a PST file, deleted the mailbox, recreated the mailbox, and imported the PST file back in.  The mail remained stuck in the Local Delivery Queue.

While rebuilding the mailbox was the first part to resolving the problem, the second part came from a blog at www.thecyberwolfe.com/blog/?p=665.  This person explained that they had to recategorize the mail so that it would get to the new mailbox by doing the following in the registry of the server: [more]

1. Stop the SMTP service.
2. Open Regedit and navigate to the following key:
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SmtpSvc
3. Create a subkey named “Queuing”
4. Select Queuing and on right hand pane create new dword value with name “ResetMessageStatus” with value 1 in hexadecimal.
5. Restart the SMTP service – check the queues and see if mail is being delivered. Also check the account mailbox at this point.
6. Once all the mails are delivered to that user, stop the SMTP service and change the value for “ResetMessageStatus” to 0 and start the SMTP service.