Техподдержка посоветовала не удалять письмо и оставить его в архиве.

Техподдержка is a common shortened form of техническая поддержка, meaning technical support.

It is very common in everyday Russian, especially in IT, customer service, email, and chat contexts. It is slightly less formal than the full техническая поддержка, but still completely normal and standard.

Because it is a shortened noun ending in -а, it behaves grammatically like a feminine singular noun.

The verb посоветовала agrees with the subject техподдержка.

Here is the grammar:

• техподдержка is grammatically feminine singular
• so the past-tense verb must also be feminine singular
• that gives посоветовала

So even though technical support may refer to a team of people, Russian treats техподдержка as one singular noun, and the verb follows the grammar of the noun, not the real-world number of people.

This is a question of aspect.

• посоветовала is perfective
• советовала is imperfective

In this sentence, посоветовала means that technical support gave a piece of advice as a completed action. That fits the situation very well: they gave one recommendation.

If you used советовала, it would sound more like:

• she/it was advising
• she/it used to advise
• the advising is being described as a process or repeated action

So посоветовала is the natural choice here.

Russian often leaves that out when it is obvious from context.

The verb посоветовать can take a person in the dative case, for example:

• Техподдержка посоветовала мне... = Technical support advised me...
• Техподдержка посоветовала нам... = Technical support advised us...

In your sentence, that dative object is simply omitted because the context already tells you who received the advice.

This is very normal in Russian.

After посоветовать, Russian commonly uses an infinitive to say what action was recommended:

• посоветовать сделать
• посоветовать подождать
• посоветовать не отвечать

So посоветовала не удалять письмо и оставить его в архиве literally has the structure:

• technical support advised
• not to delete the email
• and to leave it in the archive

Russian does not need a word like to before the infinitive. The infinitive itself is enough.

You could also rephrase it with a full clause, for example:

• Техподдержка посоветовала, чтобы я не удалял письмо...

But that is longer and less neutral here. The infinitive construction is the most natural one.

This is one of the most useful things to notice in the sentence.

• удалять is imperfective
• оставить is perfective

That combination is very natural here.

не удалять

With negative advice or prohibition, Russian very often uses the imperfective:

• не делай
• не открывать
• не удалять

Here не удалять письмо means do not delete the email / avoid deleting it. The focus is on not performing that action at all.

оставить

The verb оставить is perfective, so it focuses on the result:

• leave it there
• keep it there
• make sure it remains there

So the sentence is structured like this:

• don’t do one action: не удалять
• do achieve another result: оставить его в архиве

That is why the aspect choice feels very natural.

Because его is the accusative form of the pronoun referring to письмо.

Step by step:

• письмо is neuter singular
• the nominative pronoun for it is оно
• but after оставить, you need the direct object
• so the pronoun changes to его

So:

• оно = it
• оставить его = leave it

This can be confusing because письмо itself does not visibly change in the accusative:

• письмо = nominative
• письмо = accusative

But the pronoun does change:

• оно → его

Because в архиве shows location, while в архив would suggest movement toward a destination.

Here:

• в архиве = in the archive
• в архив = into the archive

In this sentence, the idea is leave it in the archive / keep it in the archive, so Russian uses в + prepositional case:

• архиве

That is why the ending is -е.

Compare:

• оставить письмо в архиве = leave the email in the archive
• переместить письмо в архив = move the email into the archive

It can definitely mean an email archive or archived section in a digital system.

In this sentence, most learners should understand архив as something like:

• the archive folder
• archived mail
• the archive section of a mailbox or system

Russian uses the same word архив both for physical archives and digital ones, and the context makes the intended meaning clear.

The word order is natural and neutral, but it is not completely fixed.

The sentence gives the advice in a logical order:

1. не удалять письмо
2. оставить его в архиве

That makes it easy to process: first, don’t delete it; second, keep it archived.

Russian word order is flexible, so other versions are possible for emphasis, but this version sounds very normal and straightforward.

For example, moving письмо earlier could add emphasis:

• Техподдержка посоветовала письмо не удалять...

That is possible, but the original sentence is the most neutral and standard-sounding.