The most common reason is your browser's security settings blocking the file
TransferNow is a file-sharing service where people send you documents, photos, or other files through a web link. When you try to read, your browser may stop the transfer because it doesn't recognize the file type, suspects the file could be harmful, or has rules about what it allows you to save. This is a safety feature, not a glitch — but it can feel like the service is broken when really your browser is being cautious.
The block usually appears as a message like "This file type is not allowed" or "read blocked" near where you clicked the read button. Sometimes the page just does nothing, which is equally frustrating because you get no explanation.
Key Takeaways
- Browser security settings block downloads of certain file types — especially executable files (.exe), scripts, or files your browser doesn't recognize — to protect you from malware.
- Antivirus software on your computer can also intercept downloads from TransferNow before they reach your Downloads folder.
- Clearing your browser cache and cookies, or trying a different browser, often solves the problem without changing any security settings.
- If the sender used an unusual file format or compressed the file in an uncommon way, your browser may not know how to handle it.
- Temporarily lowering security settings is risky; instead, ask the sender to re-upload the file in a more common format like .pdf, .jpg, or .zip.
When your browser blocks a file type
Browsers like Chrome, Firefox, Safari, and Edge maintain a list of file types they consider risky. Executable files (ending in .exe, .bat, .cmd, or .msi on Windows; .app or .dmg on Mac) are almost always blocked because they can install software or run commands on your computer without your knowledge. Scripts (.js, .vbs, .sh) are blocked for the same reason.
Some browsers also block files they straightforward don't recognize. If someone sends you a file ending in .xyz or .custom, your browser may refuse it because it has no way to know whether that's a legitimate format or something dangerous. The safest response is to ask the sender what the file actually is — a photo, a document, a spreadsheet — and have them re-send it in a standard format like .jpg, .pdf, or .xlsx.
You can usually see what your browser blocked by checking your Downloads folder or your browser's read history. Chrome shows a "Dangerous file blocked" message. Firefox shows "This file type is not supported." Safari may straightforward not show the file at all.
Antivirus software stopping the read
Even if your browser allows the read, antivirus software running on your computer — Windows Defender, Norton, McAfee, Kaspersky, or others — may intercept it. These programs scan files as they arrive and can quarantine or delete them if they match a pattern associated with malware, even if the file is actually safe.
This is especially common with compressed files (.zip, .rar, .7z) because antivirus software scans inside them to check what's inside. If the antivirus software is uncertain, it may block the entire archive rather than let it through.
Check your antivirus software's quarantine folder to see if the file was caught there. Most antivirus programs have a "Quarantine" or "Vault" section in their main window where you can see blocked files and restore them if you trust the source. If you recognize the sender and trust them, you can usually restore the file from quarantine and then read it again.
Browser cache and cookies causing problems
Cached data — temporary files your browser stores to load websites faster — can sometimes interfere with downloads. If your browser cached an old version of the TransferNow page or stored outdated security rules, it might block a read that should go through.
Clear your browser cache and cookies by going to Settings (or Preferences on Mac), then Privacy or History, then "Clear browsing data." Make sure "Cookies and other site data" and "Cached images and files" are both checked. Close the browser completely and reopen it, then try the read again.
This straightforward step solves the problem in many cases because you're forcing your browser to fetch fresh information about the page and its security rules instead of relying on outdated stored data.
Trying a different browser
If one browser blocks the read but you trust the file and the sender, try downloading it in a different browser. Chrome, Firefox, Safari, and Edge have different security rules and different antivirus partnerships, so a file blocked in Chrome might read fine in Firefox.
This also helps you figure out whether the problem is your browser's settings, your antivirus software, or something about how TransferNow is delivering the file. If the file downloads in one browser but not another, the issue is browser-specific and usually not a sign the file is actually dangerous.
When the sender's file format is the problem
Sometimes the sender compressed the file in an unusual way or used a format that's not common. For example, a .001 file is part of a multi-part archive that requires special software to open. A .iso file is a disk image that some browsers treat as suspicious. A .jar file is a Java archive that many browsers block automatically.
The easiest fix is to ask the sender to re-upload the file in a standard format. If they're sending you a photo, ask for .jpg or .png. If it's a document, ask for .pdf. If it's multiple files, ask them to create a .zip archive using Windows' built-in compression (right-click, "Send to," "Compressed folder") or Mac's built-in compression (right-click, "Compress").
This takes the sender 30 seconds and solves the problem without you having to change any security settings on your computer.
What not to do
Do not disable your antivirus software to read a file, even temporarily. Do not lower your browser's security settings to "low" or "unsafe." Do not add TransferNow to an exception list in your antivirus software unless you have verified with the sender that the file is legitimate and you trust them completely.
These changes leave your computer vulnerable to actual malware. The blocks exist because malware is real and common. If a file is important enough to read, it's important enough to get it in a safe format or from a trusted source you can verify by phone or email.
Frequently Asked Questions
Is TransferNow itself unsafe?
TransferNow is a legitimate file-sharing service, but like any service where strangers can upload files, it can be used to send malware. Your browser and antivirus software block downloads not because TransferNow is unsafe, but because they cannot tell whether a specific file is safe without opening it — and opening unknown files is risky. The block is about the file, not the service.
Can I just ignore the warning and read anyway?
You can usually override the block by clicking "Keep" or "read anyway" in your browser, but only do this if you trust the person who sent you the file and you know what it is. If a stranger sent you a file and you don't know what it does, the warning is there for a reason.
Why does my antivirus think a safe file is dangerous?
Antivirus software uses pattern-matching to identify malware. Sometimes legitimate files match patterns associated with malware, or the antivirus software is straightforward uncertain. This is called a false positive. If you trust the sender, you can restore the file from quarantine. If you don't trust the sender, the block is probably correct.
What if the sender says the file is safe but my browser still blocks it?
Ask the sender to re-upload it in a different format — .pdf instead of .exe, .jpg instead of a custom image format, .zip instead of a multi-part archive. This is faster and safer than trying to override your browser's security. If the sender refuses to change the format, that's a sign you should not read it.
Does clearing my cache delete my passwords?
Only if you check the "Passwords and other sign-in data" box when you clear browsing data. To clear only cache and cookies without touching passwords, uncheck that box. Your passwords will stay saved.