CF11 update 2 and SSRS The path of the item is not valid. If the report server is in native mode, the path must start with slash.

I am trying to conect to the SSRS in Native mode from CF 11 update 2 .

the request from CF is

http://myserver:80/ReportServer?/Reports/Account Level Mytest to Test&rs:Command=Render&rs:Format=csv&test_id=e9ffa43c%2d2eda%2d4081%2d9428%2d1ca8e784dc47&period_start=11%2f01%2f2013&period_end=11%2f30%2f2014

But I receive this error message:

The path of the item '%2FReports%2FAccount%20Level%20Mytest%20to%20Test' is not valid. The full path must be less than 260 characters long; other restrictions apply. If the report server is in native mode, the path must start with slash. (rsInvalidItemPath) <a href="http://go.microsoft.com/fwlink/?LinkId=20476&EvtSrc=Microsoft.ReportingServices.Diagnostics.Utilities.ErrorStrings&EvtID=rsInvalidItemPath&ProdName=Microsoft%20SQL%20Server%20Reporting%20Services&ProdVer=12.0.2381.0"

All is correct like paths and all other strings.

If execute separatly in the browser the same request it's work :

http://myserver:80/ReportServer?/Reports/Account Level Mytest to Test&rs:Command=Render&rs:Format=csv&test_id=e9ffa43c%2d2eda%2d4081%2d9428%2d1ca8e784dc47&period_start=11%2f01%2f2013&period_end=11%2f30%2f2014 

Any suggestions ?