[Urgent] Intermittently getting a "No Data Received" error in my browser when I try to save elements.

I've seen a couple forum posts about this error but no clear solutions besides editing my .htaccess file (which did not work). The error started occurring after I mistakenly had two manager windows open and saved a resource in one window and continued editing in another (long night, wasn't thinking). The first time it happened I replaced my database with a clean backup (having assumed that this misstep had somehow corrupted it) and cleared my cache manually. My site doesn't appear to be infected with any malware. However, this keeps happening from time to time when I save any one of my elements. I can't keep working with this Damocles sword hanging over me all the time, unsure whether I'll be able to save or not. Would it help to reinstall ModX on top of my existing one? Thanks in advance for any suggestions and support.

PHP Version: 5.2.17
System: Linux p3nlhg1369.shr.prod.phx3.secureserver.net 2.6.32-358.18.1.el6.nfsfixes.x86_64 #1 SMP Wed Sep 4 14:07:10 MST 2013 x86_64
MySQL ver: 5.0
ModX ver: 2.2.10-pl
Addons: Archivist, Batcher, CheckboxSortable, CodeMirror, getDate, getPage, getRelated, getResources, getUserProfiles, If, MIGX, phpThumbOf, tagLister, TinyMCE, Wayfinder

Nothing?

Is that a MODx error, or a server error?

Well i'm not sure how I would determine the difference... The ModX error log isn't returning any errors. I never know when I save an element whether it's going to go through, and it's happening in all my browsers. I've already tried upgrading my ModX — to no avail...

I have read that sometimes the web server has to be re-started to solve this. It basically means that the web server didn't return anything after the POST request. It could be that your hosting provider has made some changes to mod_security, and some POSTs are being rejected.

I don't think that your double-editing had anything to do with it; I do that all the time and it's never caused a problem.

Ok. So, I created a new subdomain for the test site, installed modx and a fresh database and began the painful task of manually copying over all of my resource and element content. As I was saving one of the newly created elements, the same thing happened. "Error: No data received". What is going on?? Tech support at my hosting site hasn't noticed anything wrong on their end... Should I try a deprecated version of ModX? I've never had this problem before on 6 different ModX sites.

Scouring Wordpress forums I think that i've uncovered the problem and you were right Sottwell, it is most likely an issue with mod_security. Apparently my service, Godaddy, has recently updated their mod_security to limit the amount of post requests a site or IP can make at a given time and if too many requests are sent, the site will crash out for a limited time. It basically blacklists your IP for a little while (usually about 30-60 seconds). Thanks so much for your insights Sottwell.

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