iZip IMG

Fix Processing, Preview, and Download Errors

Separate processing problems from browser download problems, then test with one known-good image.

3 min readLast updated 24 juillet 2026

Overview

A file can upload successfully and still fail later during processing, preview, or download. Each stage has different likely causes.

Before changing several settings, repeat the task with one small image and the default options. That baseline shows whether the problem is tied to the source file, a setting, or the browser.

Find the stage that is failing

  1. 1

    Confirm that upload completed

    Wait until the selected file is fully listed before starting the transformation.

  2. 2

    Retry with default settings

    Use one small image and avoid extreme dimensions, quality values, or a very large watermark.

  3. 3

    Check the preview

    If processing finishes but the preview is missing, reload once and test in a current browser without content-blocking extensions.

  4. 4

    Allow the download

    Check the browser download panel and site permissions. Some browsers ask before allowing multiple files.

  5. 5

    Open the downloaded file locally

    Verify the filename, extension, file size, and application used to open it. Download again if the transfer produced a zero-byte or incomplete file.

Tips for a better result

Keep the original

Do not overwrite your only source file until the output has been opened and checked.

Use moderate settings first

A successful baseline makes it easier to increase compression or dimensions safely.

Check available storage

A device with very little free space may fail to create or save a large result.

Common mistakes to avoid

Starting the same job repeatedly

Multiple simultaneous attempts can increase memory and network pressure without fixing the cause.

Judging quality from a tiny preview

Open the downloaded image at its intended size before deciding that the result is unusable.

Troubleshooting

Processing appears stuck

Wait for the active request, then retry one smaller file. Close other heavy tabs and use a stable connection.

The result looks different from the original

Check the output format, quality, dimensions, transparency, and crop or rotation settings before running the task again.

The download is blocked

Allow downloads for iZipIMG, check the browser download list, and disable a download manager that may be intercepting the file.

Frequently asked questions

Why does a converted image lose transparency?

Formats such as JPG do not support transparent pixels. Choose PNG or WebP when transparency must be retained.

Why is the downloaded file larger than expected?

Dimensions, format, detail, transparency, metadata, and quality all affect size. A conversion can increase size even when the image looks similar.

Wasn’t this the answer?

Send the tool, browser, and exact error to our support team.

Contact support

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