I have downloaded Communicator but am unable to install it. When I double-click the file, it decompresses to about **% and then the following error message pops up:
The decompression of %s failed. There may not be enough free space available in the TEMP directory.

Solution:

Following solution is designed for Windows user, if you are having these problems on a Macintosh please go to Netscape Knowledge Base Article 970808-15.

Step 1: (Create a new temporary folder)

First, check your autoexec.bat file (open autoexec.bat via text editor, not double click on it) and make sure there are two lines that reads:

SET TEMP=C:\TEMP
SET TMP=C:\TEMP

Make sure that C:\temp directory (folder) exists, or that if your Temp directory is in a different location than this example, the path is set accordingly. It is also important to make sure that the temporary folder (directory) is not damaged. If the temporary is created some time ago, you might try to rename the temp folder to tempold and re-create temp folder.

If these lines are not in the autoexec.bat file, then Windows will default to using C:\Windows\Temp as the temp directory.

You will need to restart the computer for the changes to take place.

Step 2: (check your temporary folder is clean)

You may also have some files in your TEMP directory that are causing the decompression of the archive to fail.
Usually TEMP directory is located under C:\Windows\Temp, however if you are using Windows 2000 or XP, the TEMP directory is located C:\Documents and Settings\[profile name]\Local Settings\Temp.
Using Windows Explorer, delete any files and folders you do not need from this directory. If the the Communicator install file is in this directory, move it to a different location. If a file or folder is in use then you will get a warning message, and you will not be able to delete it.

Step 3: (Antony's tip: Reduce your Hardware Acceleration.)

In your control panel, go to the Graphic Card's Hardware Acceleration, and lower it down to none. Then run the setup file again. (After running setup file, if successful, change the Graphic Card's Hardware Acceleration back.)

Still not working, try Step 4:

If you are still having problems after trying the above steps, there may be some files with the property Read Only and/or Hidden may that are causing the Problems. Search your entire drive for these files:

uninst.exe
_isdel.exe

Next, check the Properties of these files by right-clicking on them with your mouse and selecting Properties from the pop-up window. Verify only that only Archive is selected.

If there is a recently created directory beginning with a '~' (tilde) character in the same directory as the executable you are trying to run, remove it. This is an InstallShield temporary directory that was not removed. It was probably left there due to a crash.

Still not working, Step 5: (have enough disk space?)

If you're still having problems installing, make sure that you have plenty of free hard drive space.

Still not working, Step 6: (check your video's setting)

If this does not work, your video cardís driver (the software that runs the card) may be causing the conflict. As a temporary fix to this problem, set your display adapter to Standard VGA by doing the following:

1. Right-click (context click) on your Desktop and select Properties.
2. Click the Settings tab and click Advanced.
3. Select the Adapter tab, click Change, and then click Next.
4. Select the second option, "Display a list of all the drivers in a specific location, so you can select the driver you want."
5. Click Next and select "Show all hardware".
6. Write down the display adapter you are currently using.
7. Select "(Standard display types)" from the Manufacturers column. It will be the first option, so you may need to scroll to the top.
8. Select "Standard Display Adapter (VGA)" from the Models column and click Next.
9. If prompted, click Yes, then click Next, and finally click Close.
10. When you are prompted to reboot your computer, click Yes.
11. When the computer reboots, go to the homepage of your video cardís manufacturer and download the most current drivers for your card.

Reboot after taking each of these steps to ensure that the system has recognised the changes.

Tried all above methods, still not working:

Then I am sorry, you will have to re-download Netscape. Sorry.