You have just clicked on "send", but there is a spinning wheel on the Smash interface and nothing happens?
The most common reason is that Smash is being blocked by your antivirus or other software, such as adblocker.
My antivirus is blocking my transfer
If you are using antivirus software, its security rules may be too strict and cause it to consider Smash as unsafe.
If an update is available for your antivirus, installing it may remove the blockage.
If the issue persists, you can add Smash to your antivirus trusted sites. Alternatively, you can temporarily disable the antivirus while sending your files on Smash.
My adblocker is blocking my transfer
Browser extensions, especially ad blockers, are known to block uploads or downloads made through Smash.
To check whether they are causing the issue, you can disable these extensions while using Smash.