Category Archives: Windows

Stuff about Microsoft’s answer to elevator music

Using external Certificate Authority certificates in a restricted or closed environment

In this example, we’ll be using a wildcard certificate from Let’s Encrypt, obtained through their recently released wildcard certificate offering. What we’re doing The use case is that we want, for one reason or another, to use this certificate in an environment that does not have unrestricted internet access, such as a health institution or […]

How to deal with error 0xc03f6506 when upgrading stubborn Windows 10 Home Edition machines to Pro using a VLK

So, the machine auto-activates Windows 10 Home Edition at install time. No prompts, no nothing. You insert the generic upgrade key, and it throws an unhelpful error message back at you: This probably surprises nobody, but trying again, as the above message suggests, will not work for you. The solution? Stuff the install media (in […]

Shrinking a Windows 10 installation for small harddrives

Cheap Windows 10 capable devices often come with very limited internal storage space. To make use of this, it is of course crucial that Windows itself takes up as little space as possible. To combat the bloat, there’s a little known feature in compact.exe, the built-in disk compression tool, that compresses the operating system itself, […]

Making Windows keep the system clock in UTC

Some hypervisors for virtual machines do not properly support sending a fake system time to the guest operating system, thus making Windows guests display the wrong time if their timezone is set to anything except UTC. This happens because Windows, by default, keeps the system clock set to the local time. This is stupid. The […]

Finding the most expensive recent SQL queries on SQL Server

Mostly a note to self, original source here. SELECT TOP 10 SUBSTRING(qt.TEXT, (qs.statement_start_offset/2)+1, ((CASE qs.statement_end_offset WHEN -1 THEN DATALENGTH(qt.TEXT) ELSE qs.statement_end_offset END – qs.statement_start_offset)/2)+1), qs.execution_count, qs.total_logical_reads, qs.last_logical_reads, qs.total_logical_writes, qs.last_logical_writes, qs.total_worker_time, qs.last_worker_time, qs.total_elapsed_time/1000000 total_elapsed_time_in_S, qs.last_elapsed_time/1000000 last_elapsed_time_in_S, qs.last_execution_time, qp.query_plan FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) qt CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle) qp ORDER BY qs.total_logical_reads DESC — logical reads […]

Figuring out which session is blocking a query on Microsoft SQL Server (query suspended)

I was recently debugging a case where a customer’s installation was hanging due to a database lock. The issue turned out to be that the database was not set to a default transaction level of READ COMMITTED SNAPSHOT, which the product expects. Regardless, while troubleshooting the issue, I stumbled upon a very useful SQL query […]