Frequently Asked Questions
Whether you want to know more about a Nitro PDF Pro trial or need help activating your license, we have all the answers you need.
    • If you are on Nitro PDF Pro 12 or an older version such as Nitro PDF Pro 11, Nitro PDF Pro 10, or Nitro PDF Pro 9, you might not be able to re-activate your software (Error message “There was a connection issue”). This is because our activation servers no longer support older versions of Nitro PDF Pro, so your software needs to be updated to Nitro PDF Pro 13 or to the latest build of Nitro PDF Pro 12.

      If you're an individual user, you will have an option to either upgrade to Nitro PDF Pro 12 free of charge, or to upgrade to Nitro PDF Pro 13 for a discounted price. This upgrade can be run on top of your already installed license of Nitro PDF Pro. If you choose to upgrade to Nitro PDF Pro 12, please visit our downloads page and install Nitro PDF Pro Your new license will use the original serial number for its activation. If you have trouble finding your original serial number, please visit our Knowledge Base for help.

      If you choose to upgrade to Nitro PDF Pro 13, please visit our site and we will provide you with your new serial number.

      If you're a Nitro business customer, please reach out to your IT department for assistance, or submit a support ticket (Activation option for non-VIP customers) and we'll gladly assist you.

    • Before you buy Nitro PDF Pro, you have the opportunity to try our product at no charge for 14 days. During your free trial, you’ll have access to the full functionality of Nitro PDF Pro. After installation, Nitro PDF Pro will automatically be in trial mode.

      After the 14-day trial period, your version of Nitro PDF Pro will revert to “expired trial” mode. You will see this notification in the bottom right corner.

      If you would like to purchase the full version of Nitro PDF Pro, please visit our pricing page.

      Once you purchase, you will receive a serial number that allows you to activate Nitro PDF Pro on your device.

    • Nitro VIP Access (formerly known as Software Assurance) was an annual subscription that enables you to maximize your investment in Nitro PDF Pro. Although it is no longer sold, you may be a customer with this service. Here are the available support options:

      • Individual online customer: Nitro VIP Access has an SLA for individual customers as a 24-hour first-response time via email (phone support is not included)
      • Business customer: Nitro VIP Access is included with all Business subscriptions and is valid for the life of the subscription. The support SLA for Business accounts is a 4-hour first-response time via email (phone support is not included).
      • Enterprise customer: Nitro VIP Access and Nitro Customer Success are included with all Enterprise subscriptions and are valid for the life of the subscription. The support SLA for Enterprise is 2-hour first-response time.
    • The following resources are available to all Nitro customers:

      • Community Forum, where you will find a large selection of helpful topics and the opportunity to post questions and suggestions for product improvements (simply create or log in to a Community account to post suggestions). The Community Forum is the perfect platform for connecting with other Nitro PDF Pro users, as well as some of our official Nitronauts.
      • Knowledge Base, where you will find a vast selection of help articles that cover all common product questions for Nitro Pro. Check it out on our Support page.
      • User Guide, where you will find information about the functionality and features in Nitro PDF Pro.
    • Depending on your license type, there are two different ways to activate Nitro PDF Pro:

      1. Activating with our single user or business license: To activate your copy of Nitro PDF Pro, simply open the program and select the Help tab » About Nitro PDF Pro » Activate ». Please enter your serial number and click Activate.
      2. Activating with our Enterprise license: To activate your copy of Nitro PDF Pro, simply open the program and select the Help tab » About Nitro PDF Pro » Activate. In the activation window, please enter your license information, which includes your first and last name. Then, click Load from File » select your lic. file and click Activate.
    • All online orders of Nitro PDF Pro are conducted by our online reseller Cleverbridge, Inc. Payment processing and order fulfillment are done by Cleverbridge, Inc., 350 N Clark, Suite 700, Chicago, IL 60654, United States. Therefore, you will receive your purchase information from Cleverbridge, not Nitro.

    • Unless purchased directly through Nitro Sales or authorized reseller partners, Nitro is otherwise only available for purchase online at Please note that Nitro Software does not sell its products on online marketplaces, such as eBay. All copies that are available on eBay (or similar marketplaces) are pirated and unsupported and are likely to contain trojan horses and viruses. We have received many complaints regarding these cracked versions. The only official place to purchase Nitro’s award-winning software is directly through Nitro’s pricing page.

    • Upgrade: This means that a newer version of Nitro PDF Pro is being purchased, such as upgrading from Nitro PDF Pro 11 to Nitro PDF Pro 13. This can be done by entering your serial number on our Upgrade page.

      Update: This is when a newer build of the Nitro PDF Pro version you are currently using has been released. For example, updating from Nitro PDF Pro to Since updates can include bug fixes, feature enhancements, and security updates, we always recommend running the latest version of Nitro PDF Pro. Customers who have purchased a subscription to either VIP Access or, separately, Product Upgrades, will have ongoing access to product upgrades for one year after the date of purchase. Eligible customers can download the latest version here.

    • You might find the “Check for Updates” option under the Help tab within Nitro PDF Pro. As this feature currently does not work properly, we advise customers to ensure they have the latest build of Nitro PDF Pro by visiting our Downloads page. Clicking on “Download Nitro PDF Pro” will update your software to the latest version. To find what build of Nitro PDF Pro you currently have, please click on “About Nitro PDF Pro” under the Help tab.

    • Our License Portal is only valid for serial keys with three or fewer licenses. Should you have more licenses, please log a ticket with our support Team.

      If you used our License Portal, don’t have active Nitro VIP Access, and are still unable to activate your Nitro PDF Pro license, please head over to our Community Forum to notify us, so we can take a closer look.

    • We do not offer phone support at this time, as we find that communicating via email expedites troubleshooting by providing a more efficient way to share files and screenshots.

    • Please check our Server Technical Details page for all information on Nitro system requirements and deployment options.

    • Anyone has access to the content on our Community Forum. Should you wish to post something, you will need to sign up for a Community account or sign in to your existing account. Knowledge Base is a collection of articles created by our Support team to help customers maximize the powerful features in Nitro PDF Pro.

    • As our Community Forum is an online discussion platform that’s accessible to anyone, we encourage user engagement. All posts are monitored by our Support staff, who aim to respond to as many posts as possible. We are also assisted by one of our Power Users who is an expert on all things Nitro!

    • Yes! Nitro PDF Pro is now compatible with Mac operating systems. You can download a trial or purchase a one time license. Check out our pricing page to learn more.

      Please be aware the Nitro PDF Pro activation process is unique for each supported Operating System, Windows and MacOS. Thus, any License provisioned for Nitro PDF Pro on Windows cannot be used on MacOS and vice versa.

    • To ensure that Nitro PDF Pro fits our customers’ specific needs, we offer a free 14-day free trial that allows customers to try the full functionality of the product. During this trial period, you will also have full access to the Community Forum and Knowledge Base.

      You may be eligible for a refund if you purchased Nitro from our online store at and one of the following conditions applies:

      1. The product has been deemed defective by our technical Support Team
      2. A duplicate purchase has been made

      While these conditions are guidelines, all refunds are made at Nitro’s sole discretion.

      Please also check out our Refund Policy page for more information and a step-by-step guide to applying for a refund.

    • There are two ways to access Nitro Sign:

      1. In Nitro PDF Pro: Click the “Sign Up” button in the top right corner to log into your Nitro Sign account. 
      2. In Click the Nitro Sign Login button in the top right corner of our website. Then access your Nitro Sign account by entering your login details. 
Knowledge Base
Maximize your investment with informative articles about specific Nitro features, products and more.
Community Forum
Post questions, share feedback and interact with other Nitro customers and experts.
Help request
If you have Nitro VIP Access or Premium Support, you can open a support ticket and contact us directly.