Runtime Error 380: “Invalid property value,” explained and fixed

Error 380 — “Invalid property value” — means a Visual Basic program tried to set a control property to something outside its allowed range: a progress bar pushed past its maximum, a list index pointed at an item that isn't there, a size set to a negative number. In compiled business software, the trigger is usually the program's own saved data feeding it a value it can't accept.

For people who just run the program

  1. Note what you clicked right before it appeared. 380s are usually tied to one screen or one record — a specific customer, invoice, or file whose data contains an out-of-range value.
  2. Find and reset the program's settings. Many legacy apps store window sizes and last-used values in an .INI file beside the program or in its AppData folder. With the program closed, rename that settings file (don't delete it); the program recreates defaults on next launch. A window restored to an impossible position is a classic 380.
  3. Reinstall the program if settings aren't the story — damaged program files produce the same error.
  4. Try another record or file. If the error follows one specific record, that record's data is the problem — the software vendor's support can repair the data; guessing at it in the database usually makes it worse.

For people who write the code

  1. Set ranges before values. Assign Min/Max before Value on progress bars and sliders, and clamp computed values: If v > bar.Max Then v = bar.Max.
  2. Check list and combo indices. Setting ListIndex beyond ListCount - 1 — or before the list is filled — is the most common deliberate 380. Test ListCount first.
  3. Validate restored settings. Any value read from an INI file or the registry and applied to a property needs a bounds check; a hand-edited or corrupted setting is user input, and user input lies.
  4. Watch window geometry. Restoring Left/Top/Width/Height from saved values — especially negative values from a disconnected second monitor — raises 380 on form load. Sanity-check coordinates against the screen before applying them.
There is no download that fixes error 380. It's a value disagreement inside one program — between the program and its data, or between two of its own settings.

If it still happens

If a clean reinstall and fresh settings still produce 380 on every launch, the program is mismatched with something environmental — regional number formats are a quiet classic (a saved value written with one decimal separator, read back with another). Test under a standard regional format. Persistent, data-independent 380s on a supported product belong with the vendor, with the exact click-path that triggers it — that detail is the whole bug report.

Common questions

Can error 380 damage data? The error itself just stops the operation. The risk is a partially-saved record if the error struck mid-save — reopen the record afterwards and verify it looks complete.

Why did it start after the PC was moved or a monitor changed? Saved window positions. Legacy apps restore their last position and size; a position that's off-screen or negative on the new setup is an invalid property value the moment the form loads.

Related errors

Runtime Error 339 · Runtime Error 94 · Runtime Error 70