Tahoe broke use of ScanSnap ix500 scanner

There is a little glitch when you upgrade MacOS. Make sure you are using ScanSnap Home 3.3.1 to run your iX500. I'm using it with no problems. Then go to System Settings > Privacy & Security > Local Network. Then scroll down to ScanSnap Home and turn it on. Should work fine then. [For some reason the upgrade turns it off.]

According to the official Fujitsu / Ricoh (PFU) support site:

• For macOS 26 (Tahoe), you need ScanSnap Home version 3.1.1 or later. scansnap-faq.pfu.ricoh.com+1
• The legacy ScanSnap Manager is not supported on macOS 26. scansnap-faq.pfu.ricoh.com+1
• On the “Supported OS list” page, the iX500 is not clearly listed among the models with explicit MacOS 26 support under ScanSnap Home. PFU+1
• There is a known issue page for ScanSnap Home on macOS 26 — e.g., “ScanSnap Home does not work properly on macOS Tahoe 26”. scansnap-faq.pfu.ricoh.com

So in short: The manufacturer says you should use ScanSnap Home ≥3.1.1 on macOS 26. But for your model (iX500), support may be limited or ambiguous.

It’s the responsibility of 3rd parties to ensure their software is compatible with macOS updates.

https://www.scansnapit.com/en-gb/support/downloads

Maybe contact their tech support about Tahoe support. They also have a mobile app on the iOS App Store, so perhaps using an iPhone is an option.