If you have anything from where, when, or how you ordered or paid that says "Sony," you do not have a legal version of the software; therefore no support is available here according to forum moderators.

Please clarify your purchase status along with the build number as walter requested. If you have a registered Vegas Creative Software title, you should begin the troubleshooting process here:

https://www.vegascreativesoftware.info/us/forum/important-information-required-to-help-you--110457/

For me it's build 424 and once in the software it asks me to update it then then it no longer opens I specify that I bought it "finally I no longer have the impression of being have"

@Nurian - Good to see you here. Where did you obtain this Build? Sounds like you’ve got a registration issue. I’m sure Customer Support would reach-back to you. Do you want the Customer-Support Link?

I bought vegas on a small site that offers different software but the problem is that I can't put an effect on my videos because every time I want to search for an effect on the "video effect" tab the software freezes and closes on its own, I also tested with a crack version and it's exactly the same :/

and I have this error code: Unmanaged Exception (0xc0000005)

Can you give a link to the "small site" where you acquired your software? Did you pay by credit card?

Here is the link : https://www.manellasoft.uk/

Here is the link : https://www.manellasoft.uk/

Yes that's the one

€9.20 and the regular price at that site €19.99 for the current version ??? No wonder your version works similarly to the cracked version as you say.

It's best that you contact VEGAS Support (advice here), as suggested above. Remember to include your email address and the serial number for your program. We are not able to help you.

https://www.vegascreativesoftware.info/us/forum/sony-vegas-vs-vegas--119881/

@Nurian

€9.20 and the regular price at that site €19.99 for the current version ??? No wonder your version works similarly to the cracked version as you say.

It's best that you contact VEGAS Support (advice here), as suggested above. Remember to include your email address and the serial number for your program. We are not able to help you.

https://www.vegascreativesoftware.info/us/forum/sony-vegas-vs-vegas--119881/

@Nurian

But as for the error code "Unmanaged Exception (0xc0000005)" you don't know anything about it?

For me it's build 424 and once in the software it asks me to update it then then it no longer opens I specify that I bought it "finally I no longer have the impression of being have"

@Nurian
In the latest version 458, many problems have just been fixed, it is recommended to update first and then if problems persist, you are welcome to come back.
https://www.vegascreativesoftware.info/de/forum/vegas-pro-19-build-458-update-3--133380/

A tip for life: If you buy something that's only a fraction of its value to be had, it's at least a questionable purchase - and you can be sure there's a catch somewhere.
According to the old principle: "If you buy cheap, you (actually) buy expensive".