Learn Portuguese (Portugal): O processo está suspenso, o que é um problema. - The file is suspended, which is a problem.

Suspender (to suspend) is a verb with two past participles. You use the short, irregular form (suspenso) with the verbs ser and estar to describe a state or form the passive voice. You only use the regular form (suspendido) with ter or haver to form compound past tenses, such as when saying someone had suspended something.

Why do we say o que here instead of just que for "which"?

When "which" refers back to an entire previous clause or situation—in this case, the whole fact that the file is suspended—you must use o que. If you were only referring back to a specific noun right before the comma, you would just use que.

Why is processo translated as "file" rather than "process"?

While processo directly translates to "process", in legal, medical, or administrative contexts it is the standard word for a "file", "lawsuit", or "dossier" containing all the documents about a specific case.

Why use estar (está suspenso) instead of ser (é suspenso) here?