Dacă nu merge rețeaua, nu pot deschide fișierul.

In Romanian, a merge literally means to go or to walk, but it is also very commonly used to mean to work / to function for machines, systems, apps, devices, and services.

So:

• Merge rețeaua = The network works / is functioning
• Nu merge internetul = The internet isn’t working
• Nu merge imprimanta = The printer doesn’t work

This is one of the most common everyday uses of a merge.

Romanian usually uses a merge for something functioning properly, not a fi (to be).

So Romanian prefers:

• Rețeaua merge = The network is working
• Rețeaua nu merge = The network isn’t working

Using este would not express functioning in the same natural way.

Dacă means if.

In this sentence, it introduces a condition:

• Dacă nu merge rețeaua = If the network isn’t working

It is used very much like English if.

Examples:

• Dacă plouă, stau acasă. = If it rains, I stay home.
• Dacă am timp, vin. = If I have time, I’ll come.

Because each verb is negated separately.

• nu merge = doesn’t work
• nu pot deschide = I can’t open

So the structure is:

• If the network doesn’t work, I can’t open the file.

Romanian puts nu directly before the verb it negates.

Because rețeaua contains the Romanian definite article attached to the end of the noun.

• rețea = network
• rețeaua = the network

This is a major feature of Romanian: the definite article is usually a suffix, not a separate word.

Other examples:

• carte = book
• cartea = the book
• fișier = file
• fișierul = the file

This happens because Romanian often changes the form slightly when adding the definite article.

Here:

• base noun: rețea
• definite form: rețeaua

The ending -ua is the normal definite ending for many feminine nouns ending in -ea.

Similar patterns exist in Romanian, so it is something you gradually get used to rather than something to translate word-for-word from English.

After modal verbs such as a putea (can / to be able to), Romanian normally uses the infinitive directly.

So:

• pot deschide = I can open
• poți veni = you can come
• nu putem intra = we can’t enter

Using să here would generally not be the standard choice.

Pot is the 1st person singular present of a putea (to be able to / can).

So:

• eu pot = I can
• tu poți = you can
• el/ea poate = he/she can
• noi putem = we can
• voi puteți = you can
• ei/ele pot = they can

In the sentence, nu pot deschide fișierul means I can’t open the file.

Here, deschide is the infinitive form of the verb a deschide (to open).

After pot, Romanian uses the infinitive:

• pot deschide = I can open

Be careful not to confuse this with the 3rd person singular present, which can also look like deschide in many contexts:

• El deschide ușa. = He opens the door.

So the same form may appear, but its role depends on the structure of the sentence.

For the same reason as rețeaua: Romanian attaches the definite article to the noun.

• fișier = file
• fișierul = the file

The ending -ul is a very common masculine/neuter singular definite article ending.

Examples:

• calculator = computer
• calculatorul = the computer
• document = document
• documentul = the document

Yes. Romanian word order is fairly flexible, although some versions sound more natural in context than others.

The original sentence:

• Dacă nu merge rețeaua, nu pot deschide fișierul.

You could also say:

• Nu pot deschide fișierul dacă nu merge rețeaua.

Both mean essentially the same thing: I can’t open the file if the network isn’t working.

The first version puts the condition first; the second puts the main result first.

Yes, a few things may stand out to an English speaker:

• ț is pronounced like ts
  • rețea sounds roughly like reh-TSEH-ah
• ș is pronounced like sh
  • fișier sounds roughly like fee-SHIER
• The ending -ul in fișierul is often pronounced lightly in normal speech.

Also, Romanian spelling is generally quite phonetic, so once you learn the special letters (ă, â, î, ș, ț), pronunciation becomes much more predictable.

Yes, it sounds natural and normal.

Nu merge rețeaua is a very everyday way to say that the network is down or not functioning, and nu pot deschide fișierul is also completely standard.

Depending on context, a speaker might also say:

• Dacă nu merge internetul, nu pot deschide fișierul. = If the internet isn’t working, I can’t open the file.
• Dacă nu merge conexiunea, nu pot deschide fișierul. = If the connection isn’t working, I can’t open the file.

But your sentence is perfectly natural.