Category Archives: Solved Problems

Problems and solutions. Good stuff.

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: Error code 0x83FA067 means exactly the same thing, as does 0xC004F069. This probably surprises nobody, but trying again, as the above message suggests, will […]

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 […]

Creating a local Certificate Authority using OpenSSL

I was recently tasked with creating a local CA for a project, where we needed to verify custom client certificates, have the ability to revoke them at will, and we wanted to add additional custom fields to the certificates. Cool. The first stop after searching a bit was this excellent howto by Jamie Nguyen. There’s […]

Shrinking a Raspbian installation and re-enabling auto expanding for distribution of customized images

UPDATE: See the automated script at https://blog.dhampir.no/content/script-for-creating-a-compressed-image-file-from-a-raspbian-sd-card Raspbian, by default, expands to fill the SD card it finds itself on, the first time it boots. After having customized an image to your liking it would be favourable to avoid copying 16 gigabytes of data, or however large your chosen SD card is, each time you […]