Resume and bio of the author Couple of articles related to my hobby - robotics
My impressions about immigration to Australia. In Russian only. Recipes for everyday problems solving
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Andrey Mikhalchuk’s Blog

Technoblog about life

Aug 16, 2014 Fixing MacBook Pro BootCamp Black Screen of Death

So one day I’ve power on Windows on a BootCamp-enabled Windows 7 MBP Retina and after booting and making bunch of happy sounds the display went blank. No matter how many times I rebooted it the display kept looking dead. The computer was obviously running. It’s easy to check by pressing caps lock – the small LED on that button changes its status it the OS is loaded. After researching the internet I found this is a very famous issue with NVidia chipset and the only cure for this is replacing the mainboard. Bummer!
When almost all hope was all but lost I surrendered and in preparation for bringing it to the Apple Genius unplugged the laptop from power and … the display came back to life. Wow! My first thought was that NVidia chipset is still dead, but with power supply unplugged the laptop simply switched to the Intel chipset. But the thing is that Intel chipset can’t support retina resolution and the screen remained at its impressive 2880×1800 resolution, meaning NVidia were well and alive.
After opening some more time with the computer I found hilariously obvious reason for this bizarre behavior …

Jul 18, 2014 How to migrate ownCloud 6 from sqlite to MySQL

Those who do not know what ownCloud is probably should read about it here: This is an awesome tool that provides functionality similar to dropbox, but uses your own server to host the files. We all know about dropbox’s bad behavior like storing passwords on the server side, accessing your content when you don’t want it. Actually recently I was monitoring disk activity on a computer with dropbox installed on it and found that for some reason dropbox keeps reading files where it has not business to do. It was clearly configured to replicate files in its own folder, yet was reading all files on the disk. One way or another there are a lot of reasons to get rid of dropbox and switch to ownCloud. It’s cheaper, secure and can be used to store business or confidential information where dropbox fails to provide both security and confidentiality.

By default ownCloud uses sqlite3 to keep records of the files it stores and people like myself that decided to go forth with the default configuration get trapped with this configuration. Once you load more than couple gigs of data you will notice that it gets slower and sloooower and slo… Sometimes you might even experience complete freeze on the client side.

The solution to the problem is moving the data from sqlite to something mroe serious like MySQL. Both databases have SQL in their name so the migration should be easy. Unfortunately ownCloud doesn’t provide any means to automate this migrate. To make matters worse the dialects sqlite3 and MySQL use are a little bit different so you can’t feed sqlite3 database dump directly into MySQL. I saw multiple solutions to the problem migrating ownCloud 5, but nothing for OC6 so far. Here is how I migrated it in just a few simple commands:

Apr 3, 2013 How to Map Ports in Windows

Port mapping is a great feature that allows you to make almost any remote network service to work like it is running on your computer. Most people use specialized software to make it work, however there is a built-it Windows command that allows you to do exactly the same thing. Fire up windows command shell (Start->Run->cmd) and run this command:

Sep 12, 2009 Windows Vista + Firefox + Flickr (Twitter etc) = Deep freeze

So imagine you have this super-duper cool quad-core 4Gb RAM dual nvidia raid 5 computer running Vista. You’re browsing the internet enjoying/hating the ultra-sweety-psycho-aero interface and when you go to flickr/twitter/some_other_your_favorite website the entire system freezes instantly. You can’t move mouse cursor or type on keyboard and your computer gets completely stunned. That happened to me once. Actually, not once … every time I go to flickr vista dies. If you are in the same trouble and no common sense solutions (update drivers, install fixes, remove new hardware, test RAM and other stuff) are working try this:

Oct 4, 2008 How to make Delphi TFrame background transparent

I actually think this method will work for Visual Basic and other similar languages too. Here is the code for a sample frame called TfrKnob:

Sep 11, 2008 “Setup cannot continue because some system files are out of date on your system.”

“Setup cannot continue because some system files are out of date on your system. Click OK if you would like setup to update these files for you now. You will need to restart Windows before you can run setup again. Click cancel to exit setup without updating system files.”

First time I was struggling with the problem when I tried to install Dino-MITE – an excellent program for monitoring ancd controlling home dinosaurs manufactured by Ugobe. Later it appeared that the problem is more common and frequently occures with during the installation of various products written in Visual Basic.

Sep 10, 2008 Problems downloading drivers from

I don’t know exactly what causes the problem, but I’m unable to download anything from HP (Hewlett-Packard) website. I tried downloading using multiple FTP clients from different platforms and it appeared that Safari under MacOS can download the files, while Firefox under both Windows and MacOS can’t. Right now I tried to get the same file from two XP computers using FireFox and one was able to download the file, while the other one wasn’t. It’s not about firewall settings and not about passive/active mode. If someone knows the reason and how to fix the problem I’d appreciate a comment on this post.

If anyone else is experiencing the same problems use the following solution: copy the URL of the link you’re trying to download the file from (in FireFox right-click on the link and choose “Copy Link location”), paste the link into the browser’s address line, replace “ftp://” with “http://” and hit enter. This will download the file using HTTP protocol.

Mar 20, 2008 Windows Explorer: how to enable labels in the thumbnail view

Windows ExplorerSo you did something and your windows explorer is now displaying thumbnails without labels?

Here is how to cure it: switch to any other view mode and then switch back to thumbnail view while holding shift key. Nice! How many tiny features like this one windows hides inside?

Feb 7, 2008 How to enable filmstrip view in Windows Explorer (Windows XP)

Windows explorer in XP has very nice feature of displaying folder contents as a filmstrip. It is very handy to browse lots of images. Unfortunately the logic of turning it on and off this feature doesn’t perfectly match the reality. Here’s explanation how you can enable filmstrip view for your folder

Feb 6, 2008 Solving “The server you are connected to is using a security certificate that could not be verified.” problem

Uff that was tough one … If you decided to make your mail communications more secure you probably switched on SSL option in your mail client for POP3/IMAP/SMTP servers. There is a good chance you will get one of those errors that sound like

The server you are connected to is using a security certificare that could not be verified.
A certificate chain processed, but terminated in a root certificate which is not trusted by the trust provider.
Do you want to continue using this server?

I spent way too much time solving the problem because what was just annoying message in Outlook appeared to be serious problem in MacMail. It was not capable of working correctly with that problem. In addition to that I tried to solve the problem using Plesk 8.2 that was a mistake. It appeared that whatever you do with certificates in Plesk that doesn’t affect the mail. So here is the solution for the problem:

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