The forum loads and I can browse around, but threads can not be read.
This is the message:

Database error in vBulletin 3.7.1:

Invalid SQL:

SELECT a.*, au.*, post.userid, post.postid
FROM post AS post
INNER JOIN award_user AS au ON (au.userid=post.userid)
INNER JOIN award AS a ON (a.award_id=au.award_id)
WHERE 1=1
AND post.postid IN (0,864427,864429,864430,864431,864433,864523)

GROUP BY au.issue_id
ORDER BY a.award_displayorder ASC;

MySQL Error : Can't create/write to file '/tmp/#sql_53de_0.MYI' (Errcode: 13)
Error Number : 1
Request Date : Tuesday, May 25th 2010 @ 03:53:17 AM
Error Date : Tuesday, May 25th 2010 @ 03:53:17 AM
Script : http://www.mumsmeeting.com/showthread.php?p=864523
Referrer : http://www.mumsmeeting.com/
IP Address : xxxxxx
Username : "my name"
Classname : vB_Database_MySQLi
MySQL Version : 5.0.90-community

Are you using some sort of award hack?

Yeah I am, I installed it ages ago.

--------------- Added [DATE]1274780125[/DATE] at [TIME]1274780125[/TIME] ---------------

I just disabled the award hack and now my forum seems to be working again.
Thank you.

I didn't edit the hack and haven't given anyone an award for ages, do you have any idea why it could be affecting my forum now?

The error is:
MySQL Error : Can't create/write to file '/tmp/#sql_53de_0.MYI' (Errcode: 13)

This means that MySQL can not create a temporary table for sorting when needed. You should try to either:
- reboot the server
- Clean up you /tmp directory
- Check permissions on the /tmp directory

You might need to contact your host about this.

Disabling 1 product doesn't ensure that you will not run into the same problem later.

As I have not seen that hack, I have no idea what is going on. I would post about it in the thread and see if anyone else has run into any problems.

I would also follow Marco's advice and contact the host with the error and see what is going on with the /tmp directory.

I've contacted the host but no reply yet.
The hack is called Yet Another Award System 3.6

The site is working ok but still getting error when clicking on usercp

Database error in vBulletin 3.7.1:

Invalid SQL:

SELECT pm.*, pmtext.*, userlist_ignore.userid AS ignored
,icon.iconpath, icon.title AS icontitle
FROM pm AS pm
INNER JOIN pmtext AS pmtext ON(pmtext.pmtextid = pm.pmtextid)
LEFT JOIN userlist AS userlist_ignore ON
(userlist_ignore.userid = 2 AND userlist_ignore.relationid = pmtext.fromuserid AND userlist_ignore.type = 'ignore')
LEFT JOIN icon AS icon ON(icon.iconid = pmtext.iconid)
WHERE pm.userid = 2
AND pm.messageread = 0
ORDER BY pmtext.dateline DESC
LIMIT 5;

MySQL Error : Can't create/write to file '/tmp/#sql_53de_0.MYI' (Errcode: 13)
Error Number : 1

According to this:

http://serverfault.com/questions/848...myi-errcode-13

It looks like your permissions on /tmp are wrong. You will need to contact the host and have them check that out.