This is a solution, not a question. I had to do quite a bit of research to come up with a procedure to fix this headache. Hopefully this post will make it easier for the next person who gets this error.
Platform: Linux.
Problem: All of the 'Administer' pages, except 'Administer Modules', work fine. When trying to access Administer Modules, the following error occurs: "... Zero Sized Reply ..." (plus other miscellaneous, less relevant text).
Solution: Modify the php.ini file to allow more memory to be allocated to the Administer Modules script. To make the change, use a text editor such as vi, pico, or any other plain text editor. Masochists prefer emacs.
- Open the relevant php.ini file in the text editor. My php.ini file is /etc/httpd/438/php.ini (your mileage may vary).
- Scroll to the "Resource Limits" section. My "Resource Limits" section, from the top of the file, was down 20% at Line 236 of 1128 (character 10226).
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