Checks when setup or the printer stops

Error 1920, service PDF24 failed to start

The installer says: Error 1920. Service PDF24 failed to start. Verify that you have sufficient privileges to start system services. The classic printer needs that service. On older MSI packages the failure cancelled the whole install, even for an administrator.

1. Restart Windows so a leftover PDF24 service process is gone. Error 1053 was the related case: the service did not start because a process from an earlier install was still running.
2. Install 11.32.0. From this version the MSI no longer rolls the entire installation back when the service cannot start at the end.
3. If you are still on an older MSI and the installer cancels, run the EXE setup of 11.32.0 instead. The EXE also installs the service, and it does not cancel the whole install when the service fails to start.
4. If it still fails, keep the log. For the EXE, that is srvInst.log in the PDF24 program folder. For the MSI, run msiexec with a verbose log. Note the Windows version and the antivirus product. Those three facts are what a support thread can actually use.

File sizes and the EXE versus MSI choice are on the download page.

Antivirus quarantines the installer or update.exe

A scanner can move the new files into quarantine before the printer exists. Reported cases include Surfshark on a temp file, with the name Drop.Win32.RegStartupWin after version 11.20.1, and Sophos on update.exe in AppData.

1. Look at the file version before you restore anything. 11.20.1 is an old build. The current desktop line is 11.32.0, released 2 November 2026.
2. Right-click the installer, open Properties, then Digital Signatures. 11.32.0 signs the installer engine. If there is no signature, or the name is not the publisher you expect, do not restore the quarantined file.
3. Write down the detection name and the full path. That pair is what the scanner vendor needs. A signature makes a false positive more likely. It does not make it automatic.
4. After a clean 11.32.0 install, Java no longer leaves a temp file behind on every call. The background process deletes leftovers older than two days. Uninstall removes the PDF24 temp folders and logs, which is what older detections were pointing at.

The longer explanation is on the trust page.

The x64 installer refuses to run on ARM Windows

On Snapdragon and other Windows on ARM PCs, the x64 EXE and MSI stop on purpose. The emulated driverless printer lost every print job, so installing it would look successful and then print nothing.

1. Close the x64 setup. Do not try to force it in compatibility mode.
2. Download the ARM64 package. For 11.32.0 the EXE is 367 MB and the MSI is 468 MB. Links are on the installer table.
3. If the ARM64 installer replaces an x64 installation, it swaps the printer packages and keeps the printer names and the default printer. TWAIN sources show up again on the ARM64 build.

Remote Desktop jobs never arrive

Printing from a Remote Desktop session to a redirected PDF24 printer needs the classic PostScript printer. The driverless printer, used under Windows Protected Print, does not support that path, and it does not support custom paper sizes from the print server properties.

1. Check which PDF24 printer is installed. 11.31.0 replaced classic printers with driverless ones during update. 11.32.0 does not do that. It keeps the kind you already had.
2. On a new install, choose Legacy in the PDF printer component when you need Remote Desktop or custom paper. Administrators set PRINTERTYPE, or the features PDFPrinterDriverless and PDFPrinterLegacy, or the EXE switch /PrinterType=.
3. If Windows Protected Print is not active and the driverless printer cannot be installed, 11.32.0 falls back to the classic printer instead of leaving you with none.
4. Update an affected 11.31.0 PC to 11.32.0, then set Legacy if the redirected printer is still the driverless one.

Error 3003, driverless printer hangs

If background apps are forbidden by a Windows setting, a tool, or a policy, every job to the driverless printer failed with error 3003 and the queue hung.

1. Install 11.32.0. The installer allows the PDF24 printer packages to run in the background.
2. Sign out and back in. If a policy still blocks those packages, a note appears at sign-in.
3. Open PDF24 settings and use Fix now, which is the button offered for that block.
4. Where policy will never allow a background print package, install the classic printer instead, if Windows Protected Print is not forcing the driverless kind.

The Toolbox window stays blank

The Toolbox is a WebView2 app. No runtime means no Toolbox. The Creator, the Reader, and the PDF printer do not all depend on that window.

1. Install 11.32.0, or confirm the Evergreen WebView2 runtime is already on the PC. If the bundled runtime does not start, PDF24 uses the one installed with Windows.
2. On the MSI, WEBVIEW2=No skips the bundled runtime. Use it only when Evergreen WebView2 is already there. The bundled runtime in 11.32.0 is version 153.0.4234.32.
3. Do not use REMOVE=WebView2 by itself on a new install. In 11.31.x that style of feature list could install nothing. 11.32.0 stops with a message instead.
4. On 11.31.0 and 11.31.1, the EXE switch that was meant to drop only WebView2 deselected every component. Update to 11.32.0 before you rely on /COMPONENTS.
5. If you do not want the Toolbox at all, use 9.20.0. It has no WebView2 and no Toolbox, and the x64 EXE is 68 MB.

The PDF opened in Microsoft Print to PDF, not PDF24

Windows 10 and 11 already have Microsoft Print to PDF. It only writes a PDF. It does not apply PDF24 profiles, the assistant, auto-save, or digital letter paper.

1. After setup, open the Windows printer list and confirm a PDF24 printer is present. If the default PDF24 printer is missing, conversion through the associated program says so.
2. In the program you are printing from, choose the PDF24 printer, not Microsoft Print to PDF.
3. You can keep several PDF24 printers. Give each one a profile for a repeated job, such as PDF/A into a watched folder.
4. Shared printers from another computer, in the form of a UNC path, show up in the Reader print dialog and in the PDF printer install list as of 11.32.0. Older builds listed only local printers.

OCR says it could not open a data file

OCR runs on the PC with Tesseract. Pages are not uploaded. Older builds failed for Korean, Greek, Serbian, Azerbaijani, Uzbek, and some other languages with Could not open data file. Pages that contained only spaces were skipped as if they already had text.

1. Update to 11.32.0, where those language data files open and space-only pages are no longer treated as finished text.
2. Confirm Tesseract is installed. In 11.32.0 it is optional and on by default. Settings can point at the bundled copy, a system copy, or a path you choose.
3. For a hot folder, wait until the scanner has finished writing. The file starts once no program still has it open and the content is complete. If the tool shows Incomplete, start that file by hand.
4. If you are on 9.20.0 because of Windows 7, you do not have the 11.32.0 language fix. Move that job to a Windows 10 or 11 PC with 11.32.0 when the language pack matters.