Hello, Slava.
We are not aware of any artificial limits, but we'll investigate to determine whether it's a Cassini limitation or maybe an ASP.NET configurable request size limit that affecting the size of an uploaded file.
We'll let you know what we have found. If you have an IIS server installed on the same machine, try running your app under IIS and see if there are any differences - just to be sure we are dealing with a bug in Cassini Web Server.
Best regards,
UltiDev Team.
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