How I Debugged a phpMyAdmin 500 Error While Importing a Large SQL File on Laragon

I recently ran into a weird issue while working on a Laravel project on Windows using Laragon.

Everything was working fine until I tried to import a database through phpMyAdmin.

Instead of an SQL error, phpMyAdmin simply returned:

Internal Server Error
The server encountered an internal error or misconfiguration...

No useful message. Just HTTP 500.

My SQL file was around 97 MB, so at first I thought it was probably a PHP upload limit issue.

It wasn't that simple.

Here is how I debugged it.

1. Check which PHP configuration is actually running

From Laragon Terminal:

php --ini

Then I checked the important error settings:

php.exe -r "echo 'error_log=' . ini_get('error_log') . PHP_EOL;"
php.exe -r "echo 'log_errors=' . ini_get('log_errors') . PHP_EOL;"
php.exe -r "echo 'display_errors=' . ini_get('display_errors') . PHP_EOL;"

My output was:

error_log=D:/C-data/laragon/tmp/php_errors.log
log_errors=1
display_errors=1

One small Laragon/Git Bash issue I also found was:

type php

returned:

php is aliased to `winpty php.exe'

Because of that, commands like:

php -i | grep ...

sometimes returned:

stdout is not a tty

Using php.exe directly avoids that problem.

2. Check the PHP error log

My PHP error log was:

D:/C-data/laragon/tmp/php_errors.log

I reproduced the import error and checked it:

tail -n 50 /d/C-data/laragon/tmp/php_errors.log

Nothing useful appeared.

That was an important clue.

3. Make sure browser PHP and CLI PHP use the same php.ini

I created a temporary file:

<?php phpinfo();

Then opened it through the browser.

Important values were:

Server API: CGI/FastCGI
PHP Version: 8.4.4
Loaded Configuration File:
D:\C-data\laragon\bin\php\php-8.4.4-nts-Win32-vs17-x64\php.ini

My PHP limits were already high enough:

upload_max_filesize = 512M
post_max_size = 512M
memory_limit = 512M
max_execution_time = 36000

So the 97 MB SQL file should have been allowed by PHP.

4. Check Apache logs

I located the Apache error log with:

grep -Ri "ErrorLog" /d/C-data/laragon/etc/apache2 /d/C-data/laragon/bin/apache 2>/dev/null

In my case:

D:/C-data/laragon/bin/apache/httpd-2.4.54-win64-VS16/logs/error.log

Then:

tail -n 50 /d/C-data/laragon/bin/apache/httpd-2.4.54-win64-VS16/logs/error.log

Still nothing useful.

So I checked the access log:

tail -n 30 /d/C-data/laragon/bin/apache/httpd-2.4.54-win64-VS16/logs/access.log

And finally found:

POST /phpmyadmin/index.php?route=/import HTTP/1.1" 500 530

So the failure was definitely happening during the phpMyAdmin import request.

5. Check Laragon's FastCGI request limit

Because Laragon was using mod_fcgid, I searched its config:

grep -RniE "Fcgid|Timeout|LogLevel" \
/d/C-data/laragon/etc/apache2 \
/d/C-data/laragon/bin/apache/httpd-2.4.54-win64-VS16/conf 2>/dev/null

That led me to:

D:\C-data\laragon\etc\apache2\fcgid.conf

Inside I found:

FcgidIOTimeout 36000
FcgidConnectTimeout 16
FcgidMaxRequestLen 81310720

The important one was:

FcgidMaxRequestLen 81310720

That is only around 77.5 MiB.

My SQL file was:

ls -lh "/c/Users/Asus/Downloads/shabujglobal-crm (1).sql"

Output:

97M

So PHP allowed 512M, but Apache FastCGI only allowed around 77.5 MiB.

That mismatch can cause the request to fail before phpMyAdmin can properly process the upload.

6. Increase FcgidMaxRequestLen

Open:

D:\C-data\laragon\etc\apache2\fcgid.conf

Change:

FcgidMaxRequestLen 81310720

to:

FcgidMaxRequestLen 536870912

That gives FastCGI a 512 MiB request limit.

Then:

Save → Laragon → Restart All

and retry the import.

7. If the next error is “Maximum execution time of 300 seconds exceeded”

After fixing the request-size limit, I hit another possible bottleneck:

Fatal error: Maximum execution time of 300 seconds exceeded
in DbiMysqli.php

If you see this, do not edit DbiMysqli.php. That is only where the timeout becomes visible.

Instead, open:

D:\C-data\laragon\etc\apps\phpMyAdmin\config.inc.php

and add:

$cfg['ExecTimeLimit'] = 0;

If the file contains a closing ?>, add the line before it.

Then:

Save → Laragon → Restart All

and retry the import.

Setting ExecTimeLimit to 0 removes phpMyAdmin's execution-time limit for operations such as large imports.

In my debugging session, this was the latest issue I reached. I had not yet fully confirmed the final import after changing this setting, so treat this as the next configuration to verify if your import dies exactly at 300 seconds.

The main lesson

When phpMyAdmin gives you a generic 500 Internal Server Error while importing a large SQL file on Laragon, don't only check:

upload_max_filesize
post_max_size
memory_limit
max_execution_time

Also check these two layers:

FcgidMaxRequestLen

and:

$cfg['ExecTimeLimit']

In my case, the debugging path was basically:

97 MB SQL file
↓
PHP limits looked fine
↓
No useful PHP error log
↓
Apache access log confirmed /import returned 500
↓
FastCGI request limit was smaller than the SQL file
↓
After that, phpMyAdmin's 300-second execution limit became the next bottleneck

That is the part that can easily be missed: PHP may allow a large upload while Apache/FastCGI or phpMyAdmin still blocks it for a completely different reason.

And if you create a temporary phpinfo() file while debugging, delete it afterward.