We are currently trying to identify this problem.
It is a bit difficult since it doesn't happen all the time.

Sometimes when this happens you need to try a few times, sometimes you have to close the browser and try again or try to reset IIS (if this is possible for you).

You could also try to upload the module to the Install/Modules directory and install it with 'http://<www.domain.com>/Install/Install.aspx?mode=InstallResources'

 

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Geert Veenstra

It appears to be related to this line in the web.config file:

<httpRuntime useFullyQualifiedRedirectUrl="true" maxRequestLength="8192" requestLengthDiskThreshold="128192"/>

Up the requestLengthDiskThreshold value to something really big will work more often.  I don't know why, but just know it works better.

i changed the value at the web.config line (requestLengthDiskThreshold) but it didn't have any effect. i have to restart the iis.