Error starting apple diagnostic utility

Apple Hardware Test was pre-installed on the original Boot drive, and available on disk 2 of the Installer/Utilities disc set.

But no software was ever responsible for re-Installing Apple Hardware test back on the boot drive if you ever erased the boot drive or swapped it out.

an interested User has collected all the really-available versions of Apple Hardware test, and placed them on a GitHub site with instructions for making a bootable Diagnostic stick (not an Installer). You can likely find yours, make a bootable diagnostic stick and run it:

https://github.com/upekkha/AppleHardwareTest

However, if your fundamental problem is caused by the discrete GPU dropping out (which the MacBook Pro 6,2 is infamous for) that is generally NOT detected by Apple Hardware Test. that issue can be dealt with by a hobbyist hack that disables the discrete GPU and only uses the Integrated GPU, but your Mac can no longer support an external display.

TihonovArtem wrote:

MacBook Pro 6.2 (15-inch, Mid 2010)

Your machine does not support the Diagnostic you are trying to access.

The older AHT of long ago has been displaced by more recent macOS—and is not recoverable.

TihonovArtem wrote:

I want to diagnose the system

Diagnose implies an issue. If that is all you have—

In or out of warranty you can get a free over the counter 'Apple Service Diagnostics' test /assessment

Make an appointment for a "hardware issue"—

https://www.apple.com/retail/geniusbar/

also, what exact model MacBook Pro is this, some are not supported for Apple diagnostics.

There error is you can not access the server.

What is the bigger issue you are having that makes you want to run the Diagnostic?

TihonovArtem wrote:

can diagnostics work on an older version of mac os?

AHT locally has always been hit or miss.

Older macs with older OS X which included the DVD installer included the AHT on disc 2.