CAPTCHA stands for Completely Automated Public Turing test to tell Computers and Humans Apart. You will no doubt have seen this implemented in various web pages as an image of a visually distorted common word, which must be typed into an input field, thus proving that you are indeed a real person. This has become necessary to prevent the actions of bots, which roam the web looking for opportunities to inject spam into message boards, etc. Shown here in Figure 1 is an example of such an image. The idea is that a human user will recognize the word 'part', whereas a spambot will not.
Figure 1: A CAPTCHA image displaying the word 'part'
First, extract the files to a suitable place on the server. There are two .js files, and a folder named cimg, which contains the word images to be displayed on the logon page. Place the entire extracted jcap folder in the C:\Program Files\Microsoft\Exchange Server\ClientAccess\Owa\auth folder as shown in figure 2:
Figure 2: The extracted jcap files in the auth folder
Next, use Explorer to locate the logon.aspx file that creates the FBA logon page. This is inside the same auth folder that you just placed the jcap folder into. Before doing anything else, make a backup copy of the logon.aspx file. Right-click it, then select Copy, then right-click the folder, and then select Paste. This creates a copy of your logon.aspx file named 'Copy of logon.aspx' . If your modifications are unsuccessful, you will need to revert to this original file to restore FBA functionality. Now, open the logon.aspx using Notepad. I'm going to insert the image just above the 'Public Computer' radio button, so press F3 and search for the text rdoPblc . Assuming that you successfully found the text, insert the following just before the preceding
Enter the code as it is shown below
The result should look something like figure 3:
Figure 3: The amended contents of logon.aspx in Notepad
Next, press CTRL-HOME to go back to the top of the file, and then press CTRL-F, and search for the text
This part of the page should now look like that shown in figure 4:
Figure 4: The modified