http://www.adobe.com/support/downloads/product.jsp?product=1&platform=Windows

Acrobat 4.05 Update 2 for Windows	
Adobe Acrobat 4.05 Update 2 resolves all of the problems addressed in Update 1. (See www.adobe.com/support/salesdocs/f6ea.htm for details.) 
Update 2 is a cummulative release; you do not need to install Update 1 first.

Update 2 resolves the following problems in Acrobat 4.05, Acrobat Business Tools 4.05, Acrobat Reader 4.05, and Acrobat Fill In 4.05 for Windows:
- Security vulnerabilities due to buffer overrun attacks
- Crashes when exporting multiple pages to Level-1 EPS

Adobe recommends that you download and install this update for all Acrobat products.
System requirements
Adobe Acrobat 4.05 or Acrobat Business Tools 4.05
or Acrobat Reader 4.05 or Acrobat Fill In 4.05 for Windows.
Installation instructions
After downloading a ".exe" file in Windows, double-click on the ".exe" file to access the file's contents.
Need help with downloading? See our Downloading Help documents.

After downloading a *.exe file, double-click the *.exe file to access its contents. Need help with downloading? See our Downloading Help documents.

To install Update 2:
1. If you use Windows NT or Windows 2000, log in as Administrator.
2. Double-click the Acrobat 4.0.5 Update 2 file.
3. Follow the on-screen instructions.

Product					Acrobat	
Version					4.05	
Platform				Windows	
Filename				ac405up2.exe	
Released On				7/25/2000	
Filesize				2.8 MB	
Download the file from:	
HTTP		http://download.adobe.com/pub/adobe/acrobat/win/4.x/ac405up2.exe
Japan		ftp://ftp-pac.adobe.com/pub/adobe/acrobat/win/4.x/ac405up2.exe