Error: Chunk name is invalid

I have a site that has been recently migrated from a different server. I don't remember what PHP, MySQL, Apache version we were running on the old server but the new one has the following stats:

Linux
Apache 2.2.27
PHP 5.4.31
MySQL 5.5.39-MariaDB

And our MODX version is 2.2.5-pl (traditional).

If I try to make a new Chunk or Snippet it throws an error "Chunk (or Snippet) name is invalid", even if I try to duplicate a chunk or snippet, MODX says it can't do it?

The entire site works perfectly fine in the front end but this is driving me nuts.

Has anyone experienced anything like this before?

I'm guessing it could be permissions related? I have already run setup after the migration to make sure everything was ok. If it is permissions related has anyone any clue as to which file it could be?

Any pointers will be greatly appreciated. Thanks!

Ok, ended up upgrading to latest MODX, and life is great again!

Darn, I cried victory too soon, now when I try to save a chunk it throws a whole new error:

Error: Processor not found: update

What gives?

Why can't I create, modify or save a chunk or snippet?

Anyone have any clues?

I downloaded MODX 2.3.1 twice to make sure it wasn't corrupted, but it seems it's probably something with my server. Please at this point I'm willing to try anything.

Thanks in advance for any help.

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MODX Revolution 2.3.1
Linux
Apache 2.2.27
PHP 5.4.31
MySQL 5.5.39-MariaDB
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1. Check the mod_security settings (suhosin?) - overly strict settings can cause odd results when trying to save things. Try disabling it altogether to see if that helps.

2. Check your files and their permissions. Make sure that PHP has permissions to read files, and has permissions to write where necessary.

Thank you kindly Susan and sorry for the late reply, it suddenly fixed itself the next day, (server having a bad circuit day I guess). Anyhow I'll keep your tips handy for the future, you never know