MQSeries.net :: View topic - Welcome to the TM SIM Registration 2025 Discussion & Sup

mrmhikel890

Hey everyone,

If you?re getting this message while trying to post on the forum:

> **SQL Error : 1271 Illegal mix of collations for operation 'IN'**
> *Line : 251 ? File : functions_search.php*

Here?s what it means and how to fix it 👇

This error usually appears when your forum?s database tables are using **different text collations** ? for example, one might be using `utf8_general_ci` and another `utf8mb4_unicode_ci`. Because of this mismatch, the system can?t compare or insert words properly into the search index.

### ✅ Quick Fix Steps:

1. Log into your **database (phpMyAdmin)**.
2. Run these commands to check collations:

```sql
SHOW TABLE STATUS LIKE 'phpbb_search_wordlist';
SHOW TABLE STATUS LIKE 'phpbb_search_wordmatch';
```
3. If the collations are different, make them match (recommended: `utf8mb4_general_ci`):

```sql
ALTER TABLE phpbb_search_wordlist CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
ALTER TABLE phpbb_search_wordmatch CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
```
4. After that, **clear and rebuild the search index** in the PHPBB Admin Control Panel.

This should resolve the error and allow you to post normally again ? including threads about **TM SIM registration** and related discussions.

If you?ve fixed this issue or found another workaround, please share your experience below so others can benefit too!