Incomplete downloads of any file over 24mg

I've had an ongoing issue of incomplete downloads. I've looked at several threads that have had similar issues but what worked for them doesn't seem to be an option for me.

Here is the exact issue - Any download of a file over 24mg will simply stop mid-stream and I get the following error: "(download.xxx) could not be saved, because the source file could not be read. Try again later, or contact the server administrator." I've tried several different files (.pdf and .zip) and the same problem persists with any larger files. Smaller files (under 24mg) will download just fine, but anything that hits that size will be stopped. I've adjusted the downloads redirect and streaming settings, gzip, I've tried zipping the files with a simple name.. nothing has worked. The files are in the correct download folder, and all of the links are matched correcting in attibutes (green dot on all). The threads I've read on the subject seem to indicated the problem might be the host and their php settings. I don't have control over that issue.

So, are there any solutions to this problem other than changing hosting services/servers? Am I missing a setting that will get this to work?

Here are the server settings:
Server OS: Windows NT WEBSERVER13 5.2 build 3790
Database: MySQL 5.0.45-community-nt
HTTP Server: Microsoft-IIS/6.0
PHP Version: 5.2.6 (Zend: 2.2.0)
PHP Memory Limit: 128M
PHP Safe Mode: Off
PHP File Uploads: On
Max Size: 15M
POST Max Size: 8M
Database Data Size: 2,844 kB
Database Index Size: 573 kB

Zencart settings:
Version 1.3.8a
Download by redirect: false
Download by streaming: true (tried both w/ no change in outcome)
gzip: off

Thanks,
Matt

HTTP Server: Microsoft-IIS/6.0
Not sure what server settings would need adjusting for IIS, buut this should be a conversation between you and your host

kobra:

Not sure what server settings would need adjusting for IIS, buut this should be a conversation between you and your host

Understood. Are there any adjustments in zencart that will get my downloads to work?

Matt

Understood. Are there any adjustments in zencart that will get my downloads to work?
Not that directly affect downloading.....As I believe this to be a php function, it would be controlled by the php time out setting on the server

Slight adjustment to problem outlined in first post of this thread. The download problem is affected not by file size but by time. I've tried the download from multiple locations which have different download speeds. All timed-out at almost exactly 5 minutes regardless of how much was downloaded.

I've been working w/ my hosting company to adjust the php settings but haven't been able to change the failure point at all. The only change has been an increase in the length of time between when the download freezes and the time the error window appears.

I need some specific suggestions for my hosting company to try. I'm going to direct them to this thread in the hopes that someone has the solution.

Matt