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Wednesday, March 31, 2010

Titbits: Disabled ASP.NET handler prevents Ape from working

There have always been problems with any kind of software, when the software itself is installed correctly but doesn’t seem to work.

The same problem occured with Helicon Ape while installing on Windows Server 2003, IIS6. User had full control of config files and was able to browse the sites in IIS, but not a single rule took effect.

Investigation of the problem led us to IIS Manager/Web Service Extensions. The ASP.NET handler was disabled, which was completely blocking Helicon Ape operation.

The reason is that Ape is an ASP.NET module which can’t be run with appropriate handler “prohibited”.

One look is all it takes to find a solution to the issue – press “Allow” button for ASP.NET in Web Service Extensions:

Best regards,
Andrew & Anton, Helicon Tech Team

Thursday, March 18, 2010

ISAPI_Rewrite3 vs LinkFreeze - which is better?

From time to time we get the questions of this kind on our forum/email, so I guess it's time to show the difference to everyone.
  1. Ease of use
    LinkFreeze is the unquestionable leader by this parameter. One dialog is everything you'll deal with - all settings are set up there.

    ISAPI_Rewrite in its turn is far more complex tool - you need to be aware of (at least) the basics of regular expressions to manage it. Most of the configuration is stored in plain text files which may be edited in a special manager.

  2. Functionality
    In this characteristic the situation is quite the contrary - ISAPI_Rewrite has incomparably more features than LinkFreeze, notably:
    - rewriting URLs in any way you want (e.g. having refer to;
    - proxying (e.g. having refer to;
    - mapfiles support (e.g. having refer to;
    - filtering requests based on server variables' values, IP addresses/domain names, referers, etc.

    LinkFreeze is achieving SEO-friendliness in a different way - it allows to make query string a part of the URL, move and change file extension (e.g. having refer to but the wording of the URL remains intact (addition/replacement/deletion of URL portions is not possible).

  3. SEO efficiency
    While LinkFreeze will automatically make your links on pages look like, with ISAPI_Rewrite3 you need to either alter them manually to look like or use 301 redirects (this may slightly decrease the pagerank of the page) to SEO-friendly page names and reverse internal rewriting to the actual page name. Here's how it looks like in terms of ISAPI_Rewrite 3 syntax:
    RewriteEngine on
    RewriteBase /
    RewriteCond %{QUERY_STRING} ^param_id=(\d+)$ 
    RewriteRule ^real_page\.aspx$ seo_page-%1.html? [NC,R=301,L] 
    RewriteRule ^seo_page-(\d+)$ real_page.aspx?param_id=$1 [NC,L]
    So, the key difference is that LinkFreeze changes links on pages and ISAPI_Rewrite doesn't!

  4. Windows versions supported
    LinkFreeze supports Windows NT 4 (IIS 4), Windows 2000 (IIS 5), Windows XP (IIS 5.1) and Windows 2003 (IIS 6).

    ISAPI_Rewrite3 supports Windows 2000 (IIS 5), Windows XP (IIS 5.1), Windows 2003 (IIS 6), Windows Vista (IIS 7), Windows 2008 (IIS 7), Windows 7 (IIS 7.5) and Windows 2008 R2 (IIS 7.5).

    If you are the lucky user of IIS7 (7.5) and need ISAPI_Rewrite/LinkFreeze capabilities, you can benefit from using Helicon Ape tool which includes mod_rewrite and mod_linkfreeze as well as a bunch of other helpful modules and functions.
Hope this article favored better understanding of the products capabilities and peculiarities, and you choice will be more conscious.

Best regards,
Anton, Helicon Tech

Wednesday, March 10, 2010

Titbits: Plus sign in IIS7

This seems to be a known issue, but I'll cover it once again just in case...

So, after fresh install of IIS7 you are likely to notice that requests containing plus ('+') character are not accepted.
The issue is that by default IIS is set to not accept double escape sequences. Let's fix it.

Open IIS Manager, go to Request Filtering page and open Edit feature settings... dialog.
Now check the Allow double escaping option and press OK.
Note! The same can be set directly in web.config using the following code:
<?xml version="1.0" encoding="UTF-8"?>
            <requestFiltering allowDoubleEscaping="true" />
That done, refresh the page in the browser and you'll have it handled correctly.
Hope you'll find this tip helpful.

Best regards,
Anton, Helicon Tech Team