no cached version available for offline mode

At office, I am behind a proxy. The internet access is restricted.

So I performed a gradle sync at home and copied the folder ".gradle" present at C:\Users\username.gradle from my home PC to the same location on my office PC.

Now on my office PC, I set gradle in Android Studio to "Work Offline" but still whenever I try to perform a gradle sync, I get an error stating

Error: Could not download google-services.jar (com.google.gms:google-services:3.0.0): No cached version available for offline mode

However on digging through the ".gradle" folder I was able to locate the google-service.jar file at

C:\Users\username\.gradle\caches\modules-2\files-2.1\com.google.gms\google-services\3.0.0\32b833222c886ecfb37d79b1a05ce1eddb702db1

I am not sure how to proceed. Please help.

I had to dig for this a long time in the 2019.2 version. This option has moved in the UI. It is now in the toolbar of the gradle tools:

see JetBrains documentation at https://www.jetbrains.com/help/idea/jetgradle-tool-window.html#offline

This Error occurs when in your Android Studio's Gradle Tools Offline Mode option is Enabled.

When Enabled it lookes like this.

To fix it, you can Disable mode by clicking on the option shown in below screenshot.