How do I open DICOM files on Windows?#
- In File Explorer, copy the complete study from the CD/USB into a new Desktop folder. Keep DICOMDIR and all neighboring image folders together.
- Open the DICOM viewer in a current browser.
- Drag the Desktop copy into the drop zone. Wait for the import to finish and select a series.
Step 1 — Don't run the hospital's viewer#
A disc may include Viewer.exe, StartViewer.bat, or autorun.inf. These belong to the bundled application. If it will not start, open the original DICOM images in another viewer without running the launcher or bypassing Windows security warnings.
Step 2 — Find the DICOM folder#
Insert the CD or plug the USB. Open File Explorer (Win + E), click the disc/USB in the left sidebar. Look for a folder called DICOM, IMAGES, IMG, or the patient's name. That folder is what you want, not the .exe file next to it.
Step 3 — Copy to Desktop#
Create a new folder on your Desktop. Copy the complete disc contents into it with Ctrl + C and Ctrl + V, including DICOMDIR and its neighboring folders. Wait until copying finishes before importing.
Step 4 — Open the browser page#
Open the DICOM viewer in a current Chrome, Edge, or Firefox browser. Keep your browser up to date; Internet Explorer and legacy Edge are not supported.
Step 5 — Drag the folder in#
Drag the Desktop copy onto the drop zone, or click 'Choose folder' and select the copied parent folder. Watch the progress bar; loading time varies with the number of files, encoding, browser, and computer. Keep any error message if a series fails to load.
Step 6 — Use the viewer#
Use the slice slider or left/right arrow keys to browse slices, then choose another series in the sidebar. In single view, the mouse wheel zooms. PNG export, compare side-by-side, and ZIP share package are all included in the free DICOM viewer at no cost.
Why won't DICOM files open on Windows?#
- SmartScreen blocked the hospital's viewer
- You do not need to bypass the warning to use the original images. Copy the complete study and open it in a DICOM viewer.
- File Explorer can't find the DICOM folder
- Look at the disc contents in File Explorer. Files can have no extension and folders can use unfamiliar names. If there are no image files, ask the imaging center for a plain DICOM export; changing protected-system-file settings is not needed for this workflow.
- Drag doesn't do anything on Edge at work
- Corporate or school PCs sometimes block file-system access in the browser. Use the "Choose folder" button instead of dragging, or try a current Chrome, Edge, or Firefox browser.
- My laptop has no CD drive
- Use a compatible external USB disc drive, copy the disc on another computer, or ask your imaging center for a USB copy or download link.
Which files should I keep together?#
Copy the whole disc into one new folder, including DICOMDIR and all image folders beside it. Keep their names and subfolders unchanged. The index alone has no image pixels; files named IM000001 can be valid images even without a .dcm extension. Our DICOMDIR guide shows what belongs together.
If your scan arrived as a download, follow the Mac and Windows ZIP instructions before choosing the extracted folder.
What should I check if my scan still will not open?#
| What happens | What to try |
|---|---|
| No files load after a drop | Use the folder picker and select the copied parent folder. Check that it contains actual image files. |
| Only a report or DICOMDIR appears | Ask the sender for the complete DICOM study, including its image folders. |
| Only one series appears | Check the series list and compare the copied folder with the original. One loaded series does not prove the export is complete. |
| A frame produces a decoding error | Keep the exact message. Try the original file in another compatible viewer or request a fresh export. |
See the DICOM troubleshooting guide for blank images, incomplete downloads, and browser errors. Use a desktop or laptop and a viewer window at least 1200 pixels wide; a small-window notice is different from a damaged-file error.
Common questions#
Does this work on Windows 7 or 8?
Use a supported operating system with a current Chrome, Edge, or Firefox browser. We do not promise compatibility with legacy Windows versions.
Do I need to be admin on my work laptop?
Nothing installs, but workplace policies may restrict file access. Ask your administrator if the page or folder picker is blocked.
Can antivirus block it?
Security software or workplace policies can restrict websites or local file access. Keep those protections enabled and ask your administrator, or use your own computer.
Does this work offline?
You can continue viewing an already loaded study while its tab stays open. Load the intended study and try the features you need while online first: an uncached decoder or feature may still require a connection. Loading the page once does not guarantee full offline use after reopening it.
Do my files upload anywhere?
Your original scan files are read locally on your device without a scan upload. Small series thumbnails, library entries, and settings can remain in your browser after you close the tab. In Settings, “Clear thumbnail cache” removes preview images; “Reset library” resets series names, hidden entries, and some library preferences. To remove all data stored by this site in your browser, clear its site data in your browser settings.
Can I view my scan on my phone?
No. The viewer needs a browser window at least 1200 pixels wide to show images alongside the series list. Use a laptop or desktop, or a tablet only if its browser window meets that width. Rotating an iPad to landscape does not guarantee enough space. Guides remain available on smaller screens.