Introduction
Any module installer that is created using distutils (bdist_wininst) is very likely to produce this error. The problem is that it only detects 32bit installations of Python on 64bit Windows machines. Or more technically, 32bit versions of Python create the following registry path

HKEY_LOCAL_MACHINE\Software\Wow6432Node\Python\PythonCore

while 64bits versions create a slightly other registry path which is

HKEY_CURRENT_USER\Software\Python\PythonCore

When any 32-bit module setup is started (with a Python 64-bit on your system), it first checks whether the first path exists, while instead it should check the second (which does exist).

There are basically three ways of solving this:

• You can install a 32-bit Python version
• or install a 64-bit version of your module
• or adjust the registry such that it really sees that a 64bit Python is installed

I will of course elaborate on the last two options.

Install a 64-bit version of your module

You can find many module binaries here. Choose a 64-bit version and install it. This is the most clean way of fixing the problem.

If your module is not in the list, then try the alternative below.

Fix by adjusting the registry

So the dirty way is to do the following adjustments in the registry:

1. Run regedit.
2. Locate the path: HKEY_CURRENT_USER\Software\Wow6432Node\
3. Create keys in this path: Python\PythonCore\2.7\InstallPath
4. Modify the “(Default)“, which is initially empty, to the path where Python is located, for example “C:\Python27\”.
5. You are done. Exit and retry the setup that gave the error.

You can alternatively create a .reg file (for example fix.reg) that will do the above steps automatically. Put exactly the following in it:

Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Python\PythonCore\2.7\InstallPath]
@="C:\\Python27\\"

If you are lazy, then you can also download this file, unpack the registry file and just run it.

I needed the lxml library on a machine for some python script that I coded earlier. I tried using easy_install by doing

easy_install lxml

but then I got the following error:

Searching for lxml
Reading http://pypi.python.org/simple/lxml/
Reading http://codespeak.net/lxml
Best match: lxml 2.3.3
Downloading http://lxml.de/files/lxml-2.3.3.tgz
Processing lxml-2.3.3.tgz
Running lxml-2.3.3\setup.py -q bdist_egg --dist-dir c:\users\edin\appdata\local\
temp\easy_install-9sxhlm\lxml-2.3.3\egg-dist-tmp-pjbtkm
Building lxml version 2.3.3.
Building without Cython.
ERROR: 'xslt-config' is not recognized as an internal or external command,
operable program or batch file.

** make sure the development packages of libxml2 and libxslt are installed **

Using build configuration of libxslt
warning: no files found matching 'lxml.etree.c' under directory 'src\lxml'
warning: no files found matching 'lxml.objectify.c' under directory 'src\lxml'
warning: no files found matching 'lxml.etree.h' under directory 'src\lxml'
warning: no files found matching 'lxml.etree_api.h' under directory 'src\lxml'
warning: no files found matching 'etree_defs.h' under directory 'src\lxml'
warning: no files found matching 'pubkey.asc' under directory 'doc'
warning: no files found matching 'tagpython*.png' under directory 'doc'
warning: no files found matching 'Makefile' under directory 'doc'
error: Setup script exited with error: Unable to find vcvarsall.bat

I tried installing libxml2 and libxslt, but it resulted in similar errors.

Searching for libxml2
Reading http://pypi.python.org/simple/libxml2/
Couldn’t find index page for ‘libxml2′ (maybe misspelled?)
Scanning index of all packages (this may take a while)
Reading http://pypi.python.org/simple/
No local packages or download links found for libxml2
Best match: None
Traceback (most recent call last):
File “C:\Python27\Scripts\easy_install-script.py”, line 8, in
load_entry_point(‘setuptools==0.6c11′, ‘console_scripts’, ‘easy_install’)()
File “C:\Python27\lib\site-packages\setuptools-0.6c11-py2.7.egg\setuptools\com
mand\easy_install.py”, line 1712, in main
File “C:\Python27\lib\site-packages\setuptools-0.6c11-py2.7.egg\setuptools\com
mand\easy_install.py”, line 1700, in with_ei_usage
File “C:\Python27\lib\site-packages\setuptools-0.6c11-py2.7.egg\setuptools\com
mand\easy_install.py”, line 1716, in
File “C:\Python27\lib\distutils\core.py”, line 152, in setup
dist.run_commands()
File “C:\Python27\lib\distutils\dist.py”, line 953, in run_commands
self.run_command(cmd)
File “C:\Python27\lib\distutils\dist.py”, line 972, in run_command
cmd_obj.run()
File “C:\Python27\lib\site-packages\setuptools-0.6c11-py2.7.egg\setuptools\com
mand\easy_install.py”, line 211, in run
File “C:\Python27\lib\site-packages\setuptools-0.6c11-py2.7.egg\setuptools\com
mand\easy_install.py”, line 434, in easy_install
File “C:\Python27\lib\site-packages\setuptools-0.6c11-py2.7.egg\setuptools\pac
kage_index.py”, line 475, in fetch_distribution
AttributeError: ‘NoneType’ object has no attribute ‘clone’

In one of my previous posts I pointed out how you can solve a similar problem with a missing vcvarsall.bat error, but unfortunately that approach did not solve my problem. Compiling the sources from the ground up was a too intensive job (which I might try to figure out in the future), so I chose the easy path.

The issue was solved by installing these packages from this site which lists a lot of (unoffical) Windows binaries for Python. Everything suddenly started to work as it should.

Introduction

There are numerous ways to share your files. This includes the usual mail, Windows Live Messenger, file-hosting sites like RapidShare, Dropbox, FTP and many other ways.

However, all have the following problem. Lets say that you want to share some REALLY big amount of data with someone, like for example 5GB or maybe even 20GB. In that case all of the above mentioned ways of sharing have serious drawbacks.

Windows Live Messenger is often very slow, can share only a few files at a time and does not support resume on sending files (which basically means that if for example your connections dies out while having 99% of your file already sent, you have to send the file all over again!). File-hosting sites like RapidShare, MegaUpload and similar sites have file size limits so that you need to upload big files by splitting it in different parts that are withing this limit  and so on (which is also the case if you use Dropbox). FTP does not pose a limit on the number or size of the files, but it again does not offer a resume of a download like Windows Live Messenger. Other drawbacks of all these type of methods  is the requirement of some initial setup, technical knowledge, user registration on websites, ads, etc.

How to send files by using µTorrent

µTorrent is a popular BitTorrent client that is used to share files by using the so called BitTorrent protocol. In µTorrent 3 it is very easy to share any of your files of any size with anyone you like. Before you proceed, you should first download and install the latest version.

There are several (more difficult) ways of doing this, but the following is by far the easiest:

Start up µTorrent and then simply drag and drop any file or even an entire folder into µTorrent. You will then get the following dialog:

When you click on “Get Link“, a tinyurl link is created which you can directly share with the person you would like to share the data.

Clicking on “Done” will put your automatically created torrent on seeding, so that now anyone (with which you share the provided link) can download your file(s). When someone opens the link a µTorrent web page will be shown that looks something like this:

On this page you can download the torrent file, the magnet link or even the file(s) directly! The other person(s) can open this torrent or insert the magnet link in theirs µTorrent client after which the download will begin.

Conclusion

Using µTorrent, or in that sense any other BitTorrent client, gives the possibility to share your files without any size limits with the further advantage of resuming your incomplete downloads at a later time. With µTorrent 3 in particular this really becomes a no-brainer.

See also the guide from the utorrent website.

* Note: To guarantee delivery of your content, your computer must be on and serving your content at the time somebody is downloading it.

There might be several reasons as to why you can’t install the .NET Framework. I had the problem while installing the framework via the Windows Update.

Symptoms
While trying to install Microsoft .NET Framework 3.5 SP1 Update for Windows 7 x86 (KB982526), Windows Update told me that the update was unsuccessful and gave me the following “useful” error:

“WindowsUpdate_800F081F” “WindowsUpdate_dt000″

You might also get several other errors similar to the following:

• an error of type 0×643
• Microsoft .NET Framework 3.5 (x64) ‘package’: [2] Error: Installation failed for component Microsoft .NET Framework 3.5 (x64) ‘package’. MSI returned error code 1601
• Microsoft .NET Framework 3.5 (x64) ‘package’: [2] Error: Installation failed for component Microsoft .NET Framework 3.5 (x64) ‘package’. MSI returned error code 1603
• Microsoft .NET Framework 3.0SP1 (x64) (CBS): [2] Error: Installation failed for component Microsoft .NET Framework 3.0SP1 (x64) (CBS). MSI returned error code -2146762496
  
• WapUI: [2] DepCheck indicates Microsoft .NET Framework 2.0SP1 (CBS) is not installed
  

“WindowsUpdate_00009C47″ “WindowsUpdate_dt000″

Solution(s)
It strongly depends on the situation and your system but you might try one of the following solutions:

• You can first try to install the System Update Readiness Tool for Windows 7 which is an August 2011 release (KB947821 - 32-bit (x86)) at this moment of writing. This should solve any inconsistencies in the Windows servicing store which may prevent the successful installation of future updates, service packs, and software. There is also a 64-bit version for Windows 7. Windows Vista: 32-bit (x86), 64-bit (x64).
• If you’re not using Windows Update, then you can try to download and install the framework manually: Microsoft .NET Framework 3.5 Service Pack 1.
• There is also a newer version of the framework which most newer applications use which might also suffice: Microsoft .NET Framework 4 (Web Installer).
• Another thing that you can try on top of all the above is to first remove all the existing .NET framework versions. Do it via Add or remove programs from the Configuration Panel. You can also try the .NET Framework Cleanup Tool.
• Do the following: Start > Run > type “services.msc”. Now check whether the Startup Type of Windows Installer is set to Manual.
• Go to Start > Control Panel > Programs > Turn Windows features on or off. Check now that the Microsoft .NET Framework 3.5.1 is checked on.
• Disable any security/antivirus software while trying to install. Usually this shouldn’t give problems, but it’s worth a try.

The fact that I’m writing this article implies that it is far from a trivial task to do this. After about 2 hours I finally found a solution that just works. Note that I’m using MiKTeX 2.9 on Windows 7, so the solution may not be working for other versions of MiKTeX and the path to the directory may vary depending on your version of windows and/or your installation preferences. The concept however is the same.

To make this work you should complete the following steps:

1. Download the package file that you want to install.
2. Create a directory in (make sure that you have admin privileges in case of Vista/7):
   • C:\Program Files\MiKTeX 2.9\tex\latex\base (for Windows XP/Vista/7 on a 32-bit Windows version)
   • C:\Program Files (x86)\MiKTeX 2.9\tex\latex\base (for Vista/7 on a 64-bit Windows version)
3. Go to Start > MiKTeX > Maintenance (Admin) > Settings (Admin) and click on Refresh FNDB.
4. Restart your LaTeX editor (in my case it was WinEdt 6.0) and now you should be able to use your new package.

Note that in step 3 I have deliberately wrote that you should chose the Admin folder, which is important if you are running Windows Vista or Windows 7, since otherwise refreshing FNDB will not result in your package being added to the database! Alternatively, you can also open the settings from the non-Admin or in some other way, but in any case make sure that the process has admin rights to update the database. If you have a more complex setup you can read this post that gives some more advanced information on how to manually add packages.

Got this compile error from LaTeX today and I really don’t have any idea what is exactly going on.

This is pdfTeX, Version 3.1415926-1.40.10 (MiKTeX 2.8)
Running miktex-pdftex.exe...
This is pdfTeX, Version 3.1415926-1.40.10 (MiKTeX 2.8) (INITEX)
entering extended mode
("C:\Program Files\MiKTeX 2.8\tex\latex\config\latex.ini"
(C:\Users\Edin\AppData\Roaming\MiKTeX\2.8\tex\generic\config\pdftexconfig.tex)
("C:\Program Files\MiKTeX 2.8\tex\latex\base\latex.ltx"
("C:\Program Files\MiKTeX 2.8\tex\latex\00miktex\texsys.cfg")
./texsys.aux found

\@currdir set to: ./.

Assuming \openin and \input
have the same search path.

Defining UNIX/DOS style filename parser.

catcodes, registers, compatibility for TeX 2,  parameters,

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
! You are attempting to make a LaTeX format from a source file
! That is more than five years old.
!
! If you enter <return> to scroll past this message then the format
! will be built, but please consider obtaining newer source files
! before continuing to build LaTeX.
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

! LaTeX source files more than 5 years old!.
l.545 ...aTeX source files more than 5 years old!}

No pages of output.
Transcript written on latex.log.
miktex-makefmt: miktex-pdftex.exe failed on latex.ini.
initexmf.exe: The operation failed for some reason.
initexmf.exe: Data: C:\Program Files\MiKTeX 2.8\miktex\bin\miktex-makefmt.exe
I can't find the default format file!

However, I did find a workaround that seemed to solve the problem and I decided to share it. Perform the following steps:

1. Open “C:\Program Files\MiKTeX 2.8\tex\latex\base\latex.ltx” (or wherever your latex.ltx resides). One alternative path that is different from mine is “C:\Program Files\MiKTeX\miktex\bin\tex\latex\base”.
2. Find “\ifnum\count@65>” and change it into “\ifnum\count@>100” (or some number larger than 100)
3. Save the file.

The real problem is not fixed, but at least you should now be able to compile your files.

Note that in Windows Vista and Windows 7 you’ll have to have administrator access to be able to overwrite this file since Program Files is a system directory. One way to accomplish this is to simply copy the file to let’s say the desktop, edit it, and then overwrite the original file with the edited file.

Assume that and . Then we trivially have

Multiply both sides with

Substract from each side

Rewrite by factorizing

Cancelling from both sides gives

Since and we get

    .

Q.E.D. ?

WordPress is a great tool for blogging, but can also be integrated in a website to provide a simple content management system. In this post I’m going to address the issue of the WordPress functions where they print the output directly and show how to catch this output in a variable.

After integrating WordPress in your code, post content can easily be queried by using the query_posts function. Along with some extra functions and setup, in the example below we show the last 10 posts orderedy by the post title (descending) from post category 3.

 
The functions the_title() and the_content() in the above example output the content directly on the web page, so it is important to place the code exactly there where you want the content to be showed.

However, in some more dynamic environments you might want to generate your content before you actually display it on the web page. That is, one can require the content to be stored in a variable that is to be printed later on or used for further processing before displaying it.

It is not possible to simply use

 
since you cannot catch an already echoed value into a variable.

To solve this problem we can use output buffering to buffer our (local) output and in that way catch our printed content. It is not necessary to understand how output buffering works exactly, so you can just look at the extended code below which demonstrates how the previously showed code example can be transformed to accomplish the desired result.

 
So essentially you start your output buffering by placing ob_start() before the actual code you want to buffer, and similarly ob_end_clean() when you want the buffering to be finished. To save all the output data you simply use the output of ob_get_contents() and place it in a variable. Note that you have to use ob_get_contents() before calling ob_end_clean() since the latter will clear the buffer.