pub file to NSX Manager.File name does not conform to the expected format. Please remove extra characters such as brackets and try againVMware NSX-T Data Center 3.x
NSX-T 3.x supports only the .MUB file.
The .PUB files were added to the upgrade workflow in later releases (VMware NSX 4.x)
Download the correct MUB upgrade bundle from the Broadcom Customer Support Portal.
Upload and use the MUB file, as it contains both the upgrade prechecks and the upgrade software.