File Extension Library


.ZL1 File Extension

  • Developer by: Check Point Software Technologies Ltd.
  • Category: Various data Files

What is an .ZL1 file?

.ZL1 file extension is created by Check Point Software Technologies Ltd.. .ZL1 has been classified as Various data Files.

.ZL1 is ZoneAlarm Mailsafe renamed ADP file

The ZL1 file extension is associated with ZoneAlarm, a personal firewall software, originally created by Zone Labs and currently developed by CheckPoint Software Technologies LTD.

One of ZoneAlarm features is MailSafe, which detects e-mail attachments and warns the user about their presence. When a potentially dangerous attachment is detected, the program quarantines the file with simple renaming of its original file extension, so it breaks the common program association function in Windows and prevents such files from being executed (or launched via associated program).

A file with ZL1 file extension originally had ADP file extension (most likely Microsoft Access project file). Simple renaming will restore the Windows associations with such file, however it is not advised, unless you are absolutely sure it safe to do.


How to open:

You can rename the ZL1 file extension back to ADP and work with the file normally. This can however be potentially dangerous, because the file was quarantined for a reason. So always re-check it with your anti-virus or anti-spyware programs before you rename the files.

How to convert:

As far as we know, this .zl1 file type can't be converted to any other file format. This is usually the case of system, configuration, temporary, or data files containing data exclusive to only one software and used for its own purposes. Also some proprietary or closed file formats cannot be converted to more common file types in order to protect the intellectual property of the developer, which is for example the case of some DRM-protected multimedia files.

How to Open .ZL1 file on different platforms

Open .ZL1 File on Windows

  • Right-click a .ZL1
  • Left-click "Open With" > "Choose another app"
  • Select the program that opens .ZL1 file and Select check box "Always use this app to open .ZL1 files" Press "Ok"

Open .ZL1 File on Mac

  • Right-click (or Ctrl + Left-click) the .ZL1 file
  • Click "Open With" > "Other.."
  • Then choose another program from the app list and press "Open"
  • Select check box "Turn on" for "Always open in app"

Open .ZL1 File on Linux

Right click on the .ZL1 file, choose "Open with" and select a program from the list above

Open .ZL1 File on iPhone

Select a file. If you don't see an application to open the .ZL1 file, tap "Share" and choose the right app.
Method 2
Save the file. Then open the app «Files». Touch and hold the file, then release your finger. You will see a black menu bar. After that tap "Share" and select an application.

Open .ZL1 File on Android

Tap the Settings icon on an Android smartphone, then select «Applications». Click the Settings icon in the upper right corner of the screen, to change the default apps.
If you want to open, edit, save or even convert .ZL1 files on Android, then your best bet is to download one of the dedicated apps available on Google Play.

How to fix problems with .ZL1 files

  1. You need to update the application that you normally use to open .ZL1 files. Only the latest version of the software supports the current .ZL1 file format
  2. You need to check the .ZL1 file for viruses. To do this, you need to scan it with a popular antivirus (Norton, Nod32, Kaspersky, Dr.Web, etc.)