Unable to write to your .htaccess or nginx.conf file.

my goodness! what a mess! I’ve just updated today, a few hours ago – the most frustrating few hours about spending almost 24 hours reconfiguring a site that crashed!

on top of all the same problems you’ve all been having, the damn plugin is constantly making me do the same settings over!

tried Wombats solution but it’s not working because it keeps undoing all my settings

rolling back to ver 3.6

Finally gave up and uninstalled it from across my sites and all my client’s sites (after manually having to delete code from htaccess files that were not removed after the uninstall).

I put in Wordfence. Smooth install, no buggy code, and the paid option already has working 2 factor identification & geoblocking. Thanks for whoever in these threads put me onto it – a much better option.

Given the increased vulnerability across the web at the moment, the risk of buggy code was too great.

I have this issue as well.
I worked through all the solutions here and the only one that worked was disabling file locking.
Its as if the plugin is locking itself out of .htaccess.
I disabled file locking, made my changes to the settings and saved them.
The htaccess file was indeed written to so I enabled file locking again since I believe it should be used to avoid the htaccess corruption issues that older version had if the site came under a big brute force attack causing multiple writes to the file.

including the new nginx rules generated by the plugin into nginx does not work for me. Nginx error:
invalid hostname or wildcard “*”

Part of the file responsible is :

location /wp-comments-post.php {

                valid_referers jetpack.wordpress.com/jetpack-comment/ *;

                set $rule_0 0;

                if ($request_method ~ "POST"){ set $rule_0 1$rule_0; }

                if ($invalid_referer) { set $rule_0 2$rule_0; }

                if ($http_user_agent ~ "^$"){ set $rule_0 3$rule_0; }

                if ($rule_0 = "3210") { return 403; }

            }

I ran into this again this morning on another site… the solution to the “It looks like another process might already be working on the file” error is to check the box at the bottom of the first section: “Disable File Locking”.

Wombat comes through again: The “Disable File Locking” solution above worked like a charm!!

This is really annoying guys – appreciate that iThemes are trying to improve their product but these issues should have been tested before the rollout given that so many people are having them. We are configuring a couple of client sites each with the “cannot write to .htaccess etc.” issue and have rolled back to V 4.08 of the plugin in the meantime since it’s working as expected.

Will hold off on upgrading any of our sites until we hear any positive feedback on this thread.

Damn. I’ve nursed about 5 sites into working with iTS, by manually editing .htaccess and/or wp-config.php, after I edit once it seems to work from then on.
But now I just created a NEW subdomain (Ubuntu 12.04 Plesk 11.5, secured with a good cert) and loaded WP 3.9 (German) and iTS 4.0.23 (no other plugins or theme), and as very first action tried to move my wp-content: Unable to write to your .htaccess or nginx.conf file.
This is really frustrating, especially since I’m using fastCGI and WP runs with the uid/gid of the Plesk Workspace, same as FTP. In other words, PHP certainly CAN write those files, but iTS won’t, even after I selected “Disable File Locking”.
I’ve not tried the Wombat solution since I just don’t see that it should be neccessary on a completely virgin installation.
Instead I deactivated iTS and installed WordFence.
WordFence (I did’nt know it before) concentrates on keeping attackers out by blocking them, and repairing compromised installations. It does NOT do a lot of the things which iTS does to prevent them from ever getting in, so I would really prefer to use iTS – IF it would work!
Finally, my sympathies to the developer(s), I’m sure you’re doing your very best and I wish you quick success with finding and repairing the root cause of these problems.