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Avast antivirus may cause problems with BSN uploads. To workaround, right click on Avast icon in the toolbar > Avast shields control > Disable for some time, then repeat the presentation upload.
Using Port 80
Some customers have firewalls or other security policies that do not allow them to use non-standard ports 9990-9994 for file uploads. In these cases, things can be working then spontaneously stop working due to an upstream change to firewall or network security policies (modern networking equipment often auto-updates without user intervention). To fix this, we have implemented server-side support for uploading files with multiple threads on port 80. To use this, you need to change the configuration file. Note that applying new settings may result in slightly slower upload speeds.
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