The most common questions, and where to look first.

Large files failing or timing out

Raise the Default max. upload size if that's the actual cap you're hitting. With remote (FTP/FTPS/SFTP) storage, the whole file travels over the network during the final "assemble and store" step, which can hit max_execution_time or a timeout on a reverse proxy/CDN in front of the site - test with a genuinely large file before relying on remote storage for big transfers.

A large upload ends with "You have created too many transfers recently"

Update to version 1.1.1 or later. Up to 1.1.0 every piece of a file counted as a transfer of its own, so an upload of roughly 50 MB or more used up the limit on transfers while it was still being sent and was refused at the last step. From 1.1.1 only a finished transfer counts. If you still see the message after updating, the visitor really has reached the limit: see Rate limiting under Security on the Configuration page.

A zip file stops with "Missing or invalid upload data"

Update to version 1.1.1 or later. Up to 1.1.0 Joomla inspected the content of every piece of an upload and rejected it when it happened to contain something that looks like a script, which stopped ordinary zip files and backups halfway. Which file types may be sent is decided by Allowed file extensions and Blocked file extensions, and that has not changed.

The upload ends with "Unexpected token '<'"

The server answered the uploader with something other than the short reply it expects. Almost always that is a PHP notice or warning printed by another extension on the site. Set Error Reporting to None under System > Global Configuration > Server, or fix the extension that prints the message.

A file type gets rejected

Check Allowed file extensions first; if it's filled in, that's the only thing being enforced. Otherwise check Blocked file extensions.

Expired transfers pile up instead of disappearing

Confirm a Scheduled Task using the Delete expired Filedrop transfers routine exists, is enabled, and that Joomla's scheduler is actually running on your hosting (cron or web-cron).

The upload page redirects to a generic URL

Create a Filedrop - Upload menu item; without one, Filedrop can't build a proper SEF URL.

Guest access password doesn't seem to apply

It only gates visitors who are not logged in. Test in a private window, or log out first.

A download link still works after it expired, or without the password

Check whether your storage folder sits inside the website root and your server runs nginx. Filedrop protects that folder with a .htaccess and a web.config, which nginx ignores, leaving the stored files reachable at their own URL and bypassing every check Filedrop performs. See Keeping stored files out of reach on the Configuration page.

An older transfer's file can't be found after renaming a Joomla user

This only affects storage folders that use the {username} placeholder, and only transfers created before Filedrop started recording the uploader's username on the transfer itself. Renaming the account moved the folder those older files were looked up in. Either rename the account back, or move the affected files into the folder the new username resolves to.

E-mails go out in one language on a multilingual site

That is the case on a site where Filedrop was first installed before version 1.1.0: its Mail Templates hold the text of the language that was active during installation, and an update leaves them as they are so your own wording is never lost. Edit the Filedrop templates per language under System > Mail Templates. A site that started with 1.1.0 or later writes each e-mail in the language that is active when it is sent. See The language of the e-mails on the Install page.

A notice about your license appears in the Filedrop administrator screens

From version 1.1.0 Filedrop tells you when something is off with your PRO license. There are three notices: your license is about to expire, your license has expired, or no download key was found. An expired license does not stop Filedrop from working, but you no longer receive updates or support. If the notice says no download key was found, enter your key for Filedrop under System > Update > Update Sites.