SYMPTOMS

Composing a message using the HTML editor within the MailEnable Web mail interface produces a FreeTextBox error.

Example:

FreeTextBox has not been correctly installed. To install FreeTextBox either:
(1) add a reference to FtbWebResource.axd in web.config:
<system.web>
<httpHandlers>
<add verb="GET"
path="FtbWebResource.axd"
type="FreeTextBoxControls.AssemblyResourceHandler, FreeTextBox" />
</httpHandlers>
</system.web>

(2) Save the FreeTextBox image and javascript files to a location on your website and set up FreeTextBox as follows
<FTB:FreeTextBox id="FreeTextBox1" SupportFolder="ftbfileslocation" JavaScriptLocation="ExternalFile" ButtonImagesLocation="ExternalFile" ToolbarImagesLocation="ExternalFile" ButtonImagesLocation="ExternalFile" runat="server" />

CAUSE

The Webresource file for ASP.NET is being blocked by a third party ISAPI filter named "ISAPI_REWRITE3" from "Helicon Tech" - http://www.isapirewrite.com.

RESOLUTION

Please consult within the Helicon documentation on how to add/edit rules to the ISAPI configuration file. The rule that needs to be added to the configuration is the following:

# Allow .axd files for ASP.NET
RewriteCond %{REQUEST_FILENAME}\.axd -f

REFERENCES

http://www.isapirewrite.com/docs/