jlopez - Wed, 2016-04-20 11:46
When using Debian or other APT based systems, the guess additions can improve the experience by providing graphical drivers and adjustments to X that allow changing resolutions. (All commands require elevation of privilege). First we must insure the header files are available
apt-get install -y linux-headers-$(uname -r)
and then we go to the Devices menu of VirtualBox and select Insert Guess Additions CD. Finally
and in that folder
jlopez - Tue, 2016-04-12 10:15
Creating a custom validation attribute for that you can use as a Data Annotation on your models is not hard, but does require a bit of care to make it work on both the server and client side. The first step is to create a class that inherits from ValidationAttribute and implements IClientValidatable. In one project, we need to validate against US and UK phone numbers.
jlopez - Tue, 2016-01-26 08:50
A frequent event log error is regarding broken performance counters. Generally the "solution" to these messages is to put one's head in the sand and ignore them, but if you prefer not seeing event log entries for things you can fix it might be possible to repair the counters using the
lodctr command to reset the offending counter. 
jlopez - Mon, 2015-11-02 10:23
The fix to many active directory issues involves the registry. RegEdit has built in support to connect to remote machines, but we normally leave the remote registry service turned off. Ironically, the recommended method usually given to turn on remote registry edits involves... editing the registry. Now this can be done via group policy, but for a one off fix, it is far easier to just start the service, make the change and turn it back off.
jlopez - Mon, 2015-10-05 11:08
Performance counters are a frequent recurring error message in Windows systems. They can indicate issues that need to be addressed, but it is very common to get errors from performance counters that are irrelevant (such as Readyboost on machines that don't use the feature). Fortunately, there is a way to manage which counters are enabled.
First, download Exctlst.exe from the Windows 2000 Resource Kit. Once installed (default location is C:\Program Files(x86)\Resource Kit) run the executable as administrator and find the counters to enable or disable.
jlopez - Tue, 2015-09-22 17:52
Ran into a situation after updating to Windows 10 from Windows 7 where Visual Studio could not debug under the full IIS stack. Turns out it is a simple fix. Simply go to %systemroot%\system32\inetsrv\config and when prompted that you don't have access, click the button that grants access. (This avoids needing to run Visual Studio as the administrator).
jlopez - Wed, 2015-09-16 10:59
Microsoft has been improving the security of the operating system bit by bit with each release. This is great news in the long run, but can catch some users who had poor security configurations in a bind when they upgrade. For example, Windows 7 allowed the default administrator account to be used by local users. Windows 10 forbids many apps from running under the default administrator account, which is a good idea as the default administrator account should be used for... administration.
jlopez - Tue, 2015-09-08 15:18
Microsoft released 1.0 of the AD Replication Status Tool a few months ago. Running it is a breeze and the system displays the status in a very readable format. Recommended for those who are curious if those "warnings" in the event log are actually transitory in nature or perhaps indicating something more important is being alluded to. Recommended as a quick check and a first step in diagnostics.
jlopez - Wed, 2015-09-02 14:01
If you have been using a certificate authority on your domain for five years, you may encounter a failure to automatically renew the certificate, which in turn causes it to be unable to renew certificates (because the sub-certs rely on the validity of the root, which is no longer valid due to expiring without renewal). The primary symptom will be Event ID 4319: "Active Directory Certificate Services could not create an encryption certificate.
jlopez - Mon, 2015-08-10 12:19
Recent we had a machine unable to log new users into it. The event log showed that the following data could not be copied into a new user profile: \\?\C:\Users\Default\AppData\Local\Google\Chrome\User Data\Default\Extensions\[random characters\[version]