Why doesn't ICQ recognize Netscape as the default browser?

Problem: "Cannot Launch Web Browser" message appears when trying to open a URL
Cause: Netscape Communicator is not properly set as the default web browser in Windows95/98
(The default web browser is the one associated with URL: Hypertext Transfer Protocol + URL:File Transfer Protocol)
Solutions: 1 2 3

Solution #1:
Netscape version 4.5 includes a setting for making itself the default web browser during installation. A simple re-install (or upgrade) should fix the problem.
Solution #2:
  1. Save the "ns4_x_fix.reg" file on your desktop or in any other folder.
  2. Double click the file.
  3. Edit the "prefs.js" file in ...Netscape/Users/<your_profile>/ and add the line: (anywhere, makes no difference) user_pref("browser.wfe.ignore_def_check",true);If, for some reason, this line is already there and says "false" then just change it to "true".
  4. Reboot your system.
Activate ICQ, right-click on the 'System' and choose any web option.
If the Browser that ICQ uses is not Netscape Communicator, please do the
following:
Right-click the "ns4.x_fix.reg" file, choose the 'edit' option and make
sure the path specified under the
[HKEY_CLASSES_ROOT\http\shell\open\command] line is the path to your
"netscape.exe" file.

If the path does not suit your system, simply change it to your path and
notice not to change the double backslashes to a regular backslash.

After you have made these changes save the changed file and double click it.

Text file of instructions | ns4_x_fix.reg

Solution #3: (for advanced users only)
The default browser in Windows95 is the browser that is associated with URL:Hypertext Transfer Protocol and URL:File Transfer Protocol.

Open Windows Explorer
Click on View
Click on Options...
Click on the File Types tab

Go to URL:Hypertext Transfer Protocol
Click on Edit
Click on Open (in Actions)
Click on Edit
Under "Application used to perform action" put
"C:\PROGRAM FILES\NETSCAPE\COMMUNICATOR\PROGRAM\NETSCAPE.EXE" -h "%1"
(or whatever directory your version of Netscape is installed in)
Under DDE Message put %1
Under Aplication put NSShell
Under Topic put WWW_OpenURL
Click on OK
Click on Close

Go to URL:File Transfer Protocol
Click on Edit
Click on Open (in Actions)
Click on Edit
Under "Application used to perform action" put
"C:\PROGRAM FILES\NETSCAPE\COMMUNICATOR\PROGRAM\NETSCAPE.EXE" -h "%1"
(or whatever directory your version of Netscape is installed in)
Under DDE Message put %1
Under Aplication put NSShell
Under Topic put WWW_OpenURL
Click on OK
Click on Close

Note: Website URLs start with http://. The second part (File Transfer Protocol) are for file transfers (ftp://) and are not as common. Adding it therefore is optional but could help.