Hi, We have knowledgeTree php application hosted on Apache/2.2.11 (Win32) mod_ssl/2.2.11 OpenSSL/0.9.8i PHP/5.2.8. The application is used by users to donwload pdf documents (average size 3MB). Very frequently we are getting issues where the download is stuck at 99% on client machines. If its stuck for 1 user than it gets stuck for all. The only choice remaining is to restart apache. We have not seen any pattern to it. Here are some configurations we have: Windows server standard 2003 x64 Intel Xeon 8GB RAM Mysql 5.0 user load: 9 concurrent users and 300 in a day. Users may on a average download 20MB of documents. PHP memory setting: 3072M http-default.conf Timeout 200 MaxKeepAliveRequests 5000 KeepAliveTimeout 10 KeepAlive On http-mpm.conf --> <IfModule mpm_winnt_module> ThreadsPerChild 1920 MaxRequestsPerChild 10 </IfModule> We have tried with all combinations of MaxRequestsPerChild from 0 - 10000. and issue still persists. During the time its stuck the server-status doesnt show anything unusal i.e. lots of idle threads. Interestingly we had the issue with just 1 user downloading 3MB documents itself. So load doesnt seem to be a factor also. CPU usage doesnt go beyond 13% RAM PF usage remains at 3.3GB We are totally baffled. The issue is not reproducible on any other environment. Any help?? Rahul