Solution
This error generally occurs because a firewall blocks the connection to the server for serial number authentication. It will be necessary to first make sure that you have the correct software versioning downloaded for your product.
If You are Installing on a Personal Computer:Temporarily disable the Windows firewall and any spyware or malware protection.
If it is a Company Computer:
- Download the correct version of the software from the NI Download Page.
- Select the Software tab and navigate to the NI LabVIEW subsection and select Download.
- Once the software download completes, try again to enter your serial number through NI License Manager.
To do this, you can navigate to the appropriate License for your product. Then enter the serial number for your product. If you need assistance finding your serial number, please reference the article
here.
If the above step's did not solve the issue, try the following:
- During the installation, when adding the serial number, try unchecking the following checkbox > Select and activate products based on my serial numbers (Internet connection required). Or choose the > I only want to evaluate products.

- Finish the installation. Once it completes, try again to enter your serial number through NI License Manager.
If the software does not accept the serial number or the error persists,
contact NI support .