Epson Scanner works but doesn't save to (any) selected folder

That sounds incredibly frustrating, especially after trying so many things. macOS permissions could be involved, but I would not assume that is the cause just yet. 

The first step is to work out whether the scan is not being saved at all or is simply ending up somewhere unexpected.

Here are a few things worth checking:

1. Check whether the file was saved elsewhere. Open Finder and search for the scanned document's filename, if known. You can also check Recents and look for files created around the time of the scan.

2. Try a different save location. Create a folder called Scanner Test on your Desktop and scan a single page to it. If that fails, try another folder in your home directory. If you are saving to an external drive, network location or cloud-synced folder, test a local folder first.

3. Check the relevant macOS permissions. Go to System Settings > > Privacy & Security >> Files & Folders and check the permissions available for your scanning app. Only consider Full Disk Access if there is a specific reason to suspect it is needed.

Apple's guide explains how file and folder access is controlled: Control access to files and folders on Mac.

4. Establish which scanning app is failing. Are you using Apple's Image Capture or Epson ScanSmart/Epson Scan 2? They handle saving differently. If possible, test the same scanner with the other application. If one saves successfully and the other does not, that helps narrow down the cause.

Apple's instructions for scanning are here: Scan images or documents using a scanner and your Mac.

5. Check Epson's software compatibility. Confirm that your exact scanner model has software compatible with your installed macOS version. I would not reinstall drivers or reset permissions until this has been checked.

The important question is what happens when the scan finishes: does it complete normally but no file appears, ignore the folder you selected, open the scan without saving it, or display an error?

If you can share your Epson model, which scanning app you are using, and what happens at the end of a scan, someone may be able to pinpoint the problem without making you repeat all the troubleshooting you've already done.

This behavior can occur due to a hidden communication block between macOS sandboxing/privacy protocols and the Image Capture background scanner drivers, or due to a corrupted preferences file.

Because you have already tried dozens of standard solutions, let’s focus on the specific, proven workarounds for this permission/saving conflict:

Reset Image Capture App Preferences

If Image Capture has registered a glitch or a faulty file path restriction, resetting its default state can force macOS to correctly save files to your designated folders again.

• Open Image Capture.
• Click on Image Capture in the top Apple menu bar.
• Select Services -> System Settings (or Preferences depending on your macOS version) and click Restore Defaults.
• Close and restart the application, select your destination folder, and try a test scan.

Bypass the "Scan To" Folder Sandboxing (The Temp Fix)

If macOS refuses to write to a specific folder because of application sandboxing restrictions, look for a folder named Image Capture_TempScan.

• When Image Capture encounters a permission block on your selected folder, it silently redirects files to a temporary folder or drops a floating Scan Results window. 
• If you see the Scan Results window pop up, you can click and drag the thumbnail directly out of that window and drop it into your target folder.

Adjust Local Network Permissions (If Scanning via Wi-Fi)

If your Epson scanner is connected wirelessly, macOS security often blocks background processes from transmitting file streams to local folders.

• Go to your Mac's System Settings > Privacy & Security > Local Network.
• Look for any entries related to Epson (e.g., EEventManager, EPSON Printer, or your specific scanner model).
• Toggle the switch off and then back on. Some users on the Apple Support Community reported that turning these off resolved the block, while others resolved it by toggling them on.

Direct Driver Launch (For Persistent Driver Blocks)

Apple acknowledged a specific "permission denied/cannot save" driver glitch involving third-party scanners and Image Capture. Forcing the driver to launch independently can clear it: 

• Quit all open applications.
• Open Finder, select Go from the top menu bar, and choose Go to Folder.
• Paste the following path and press Return:

/Library/Image Capture/Devices

• Look for an app mimicking your scanner's driver (like Epson Scanner).
• Double-click it. Nothing visible will happen, but it wakes up the background daemon.
• Re-open Image Capture and try your scan again.

The Preview Import Alternative

If you are still hitting a wall using Image Capture, it means the Apple Image Capture architecture is conflicting with the installed Epson software. 

• The Fix: Try using Apple's built-in Preview app instead. Open Preview, click File > Import from [Your Scanner Name]. Preview handles folder destination protocols differently and often writes files to directories that Image Capture blocks

(My HP OfficeJet Pro 8740 printer/scanner is named 'Mordor')

Here is what Apple has to say about solving scanning problems (maybe a bit dated given the reference to an Airport Base Station): Solve scanning problems on Mac - Apple Support

Open Image Capture.

Make sure the Scanner is present.

Set Send to: to your Desktop or preferred location.

Click the Scan button.

If the Scan is sent to or going to your Desktop, you can manually move it to the preferred folder.

How are you initiating the scan? I have had three Epson printer/scanners across at least 5 different Macs and I have never managed to get the scan function to work from the display screen of the printer despite spending hours trying to fix it. If that's what you're trying to do then my recommendation would be to give up and use the Image Capture app on the Mac to initiate the scan. I've never had any problems using Image Capture.