If you want to back up QQ, clear space, or just understand where your data lives, it helps to know how QQ organises its files on disk. Here is the practical map.
QQ data falls into two buckets. Your account data — QQ number, contacts, recent synced history — lives in the cloud and returns when you sign in. Your local data — the on-device vault — sits in folders on your disk and holds cached history, received files and per-device settings. This page is about that local side.
The primary QQ data folder lives in your user profile — commonly under your Documents area or the application-data location for your operating system. This is the vault: cached chats and the files you have received.
Files sent to you are usually stored in a dedicated sub-folder. If you share or download a lot, this is the folder that grows the most and the one to check when freeing up space.
A cache sub-folder stores temporary data — image thumbnails, previews and similar — to make QQ feel fast. It can be cleared safely after closing QQ if you need space.
Per-device preferences are stored locally too, which is why some settings don't follow you to a new device even though your account does.
Exact paths vary by operating system and QQ version, so rather than hard-coding a path that may change, the reliable approach is: fully close QQ, then search your user profile for the QQ data folder, or check the file-save location in QQ's settings, which points to where received files land. From there you can back up, clear cache, or just understand your storage.
QQ keeps a local data folder — its vault — in your user profile, typically under your Documents or application-data area. It holds cached chat history, received files and local settings, separate from the cloud account data tied to your QQ number.
Back up the main local data folder (the vault) that contains your cached messages and received files. That is the part not guaranteed to return from the cloud, so it is the folder worth preserving before a reinstall.
Clearing cache is generally safe and can fix glitches, but only delete cache after fully closing QQ, and back up the folder first if you are unsure whether it contains files you still want.
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