Hello Equipo Desarrollo,
We will need some more information in order to troubleshoot the issue that you experience. Regarding the first problem, is the file that you try to upload already opened? (in word for example). With respect to the second issue, please make sure that large file uploads are allowed in the web.config (the default limit is 4mb). Details on how to do this can be found here
. Further, do you use custom handler or use the default one?
the Telerik team