AsyncFileUpload “Cannot Access A Closed File exception

AsyncFileUpload “Cannot Access A Closed File exception

Quick post for those who may be suffering from a “Cannot Access A Closed File” exception when attempting to upload/save larger files with the AjaxControlToolkit AsyncFileUpload control…

Fix for me:

Add/edit an entry in your app’s web.config

<httpRuntime requestLengthDiskThreshold=”15360″ />

In my case this was caused by having a requestLengthDiskThreshold set too low, and was causing the file stream to close early.

8/29/2010 – *Update* Another issue you may be facing, is that your file size is exceeding the maxRequestLength setting.  To increase the size of this setting, you can define a web.config element like so (which will increase its size to approximately 2Gb allowed):

      <httpRuntime maxRequestLength="2097151" /> 

There are 3 comments .

Phil Peters —

Thanks so much. That solved our issue!

Reply »
Gaston —

Great!!! Thanks for Argentina!!!

Reply »
elmer —

Excelente muy Bueno.

Reply »

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