If you experienced problem with uploading the images in wordpress 2.5.1. Here’s the step by step solving tutorial:

- Make a notepad file. Name it test.txt

- Insert this coding to the test.txt

<IfModule mod_security.c>
<Files async-upload.php>
SecFilterEngine Off
SecFilterScanPOST Off
</Files>
</IfModule>

Save.

- Then upload it via FTP to your wordpress root.

- CHMOD it to 777

- Okay, now rename the test.txt file into .htaccess

Done. You might can’t see that .htaccess file in your FTP (some FTP can), but it is right there. And Voila! it works like magic

Updated: This tips didn’t really work smooth on wordpress’s overall performance. Such as, i was still having problem when opened the "write post", it would loading over and over and make my firefox browser frozen. So, what i did was..downgrading my WP to the old version, then installing Wordpress Automatic upgrade plugin. Then Installed the WP upgrade automatically from that plugin. And yes, it works fine!

I updated my wordpress to the newest version 2.5.1 last night and it got error like this:

Fatal error: Call to undefined function get_shortcode_regex()

Blah blah…the error is located in formatting.php page, spesifically on line 95. I tried to search the problem solving through wordpress forum, i see so many people got the same error too and they still dont have the answer. So i tried to delete the line 95 in that formatting.php page. Voila! the error has vanished suddenly. And i see no problem by deleting that error line, i hope not in the future too :p

Note: Gue pake bahasa inggris supaya kalo ada orang bule nge-search kata kunci yg sama dengan error tsb (seperti gue kemaren hehe..) bisa nyampe kesini, mudah2an bisa ngebantu yg punya masalah error pas update wordpress 2.5.1 sama kaya gw.