Internal Server Error

[ecoweb1967]

Joomla! 2.5.20 Stable
VIRTUEMART 2.0.26d

Hello everyone, I hope someone can help me
This is the error message when I want to get into Virtuemart in the control panel (Administration). I can no longer see Virtuemart
All other parts of Joomla work without problems (Menu management, user management, configuration ...)
The site works (front end) - the products you see, everything works fine.
The site works from 2014 without problems, by 2 days I have this problem

this is the error message

Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator, postmaster@mysite.com and inform them of the time the error occurred, and anything you might have done that may have caused the error.
More information about this error may be available in the server error log.

thank you all

[jenkinhill]

Joomla! 2.5.20 Stable
VIRTUEMART 2.0.26d

Have you checked for hacks to the site?  See http://forum.virtuemart.net/index.php?topic=118683

Has the host made any changes, such as a PHP update?

[ecoweb1967]

thanks Kelvyn for your quick response, I applied the two security patches but nothing has changed.
The php version on the server is 5.2.17

Thanks!

[jenkinhill]

Applied two security patches??? But your Joomla & VM versions are well out of date so really need updating. And now you say you are using PHP5.2.17 - that also is very old and known to have big security issues. See https://www.cvedetails.com/vulnerability-list/vendor_id-74/product_id-128/version_id-106044/PHP-PHP-5.2.17.html

But for the 500 error, check your server log files for the cause, or maybe install the Rupostel plugin to see if that identifies the problem. http://forum.virtuemart.net/index.php?topic=117042.0