Please note that the pSpell is a server-side application, in order for the JCK Aspell checker plug-in to work it must be installed on your server. PSPELL can be used starting with PHP version 4.3.3. If using Microsoft Windows, you must allow the web server user to execute the aspell program.

For this you must: Open the System32\ folder.
Right-click on the cmd.exe file and select the Properties item. On the Security tab select the user that runs the web server and check the Read and Execute options on the Allow column. Click OK to apply the changes.
First download the ASPELL installer as listed below.

1. Execute the downloaded file.
2. Follow the wizard's instructions: accept the licence, select the folder to install to and whether to create shortcuts or not.
3. Click Install to commence copying the required files.
4. By default the View manual check-mark is selected. When Finish is clicked, the manual page is displayed.
5. ASPELL is now installed on your system.
6. Install ASPELL 0.50 or higher as explained above.
7. Copy the aspell-15.dll file from the bin folder of your ASPELL installation into a folder in the system path, where it can be accessed by PHP.
8. Open the php.ini file with a text editor.
9. Locate the block where extensions are defined. Uncomment or add the line saying: extension=php_pspell.dll.
10. Save the php.ini configuration file and restart the web server.

ASPELL installer: