"Administrative processing" means additional review, investigation and evaluate visa applicant's eligibility to receive the visa. It could happen in F, H, L, O or any other types of visa.
This process, according to the US embassy/consulate/State Department websites, would usually take about 1-2 months. In reality, many visa applicants experience long delay.
Recently one of our clients in Shanghai experienced 6 month long delay without any decision.
Luckily in the United States, there is a legal process to address this problem. Its call federal district court lawsuit against the USCIS, State Department and the Embassy/Consulate for the unreasonable delay in its administrative processing.
We filed the lawsuit in January and the Consulate re-interviewed our client last week and issued the L-1 visa.
This type of lawsuit is absolutely very effective in compelling the US government to act.
If you have long delayed petition or application before the USCIS or the US Consulate/Embassy, please contact us.