0
# Device Management Errors
1

2
Error classes for Ledger device management operations including device state validation, connection issues, and hardware-specific errors.
3

4
## Capabilities
5

6
### Device Connection Errors
7

8
Errors related to establishing and maintaining device connections.
9

10
```typescript { .api }
11
const CantOpenDevice: CustomErrorFunc;
12
const DisconnectedDevice: CustomErrorFunc;
13
const DisconnectedDeviceDuringOperation: CustomErrorFunc;
14
const DeviceSocketFail: CustomErrorFunc;
15
const DeviceSocketNoBulkStatus: CustomErrorFunc;
16
```
17

18
**Usage Examples:**
19

20
```typescript
21
import { 
22
  CantOpenDevice,
23
  DisconnectedDevice,
24
  DisconnectedDeviceDuringOperation
25
} from "@ledgerhq/errors";
26

27
// Handle device opening failures
28
try {
29
  await openDevice();
30
} catch (error) {
31
  if (error instanceof CantOpenDevice) {
32
    console.log("Unable to establish connection to device");
33
  }
34
}
35

36
// Handle device disconnection
37
throw new DisconnectedDevice("Device was unplugged");
38

39
// Handle disconnection during operation
40
throw new DisconnectedDeviceDuringOperation("Device disconnected while signing transaction");
41
```
42

43
### Device State Errors
44

45
Errors related to device state validation and expected device modes.
46

47
```typescript { .api }
48
const DeviceOnDashboardExpected: CustomErrorFunc;
49
const DeviceOnDashboardUnexpected: CustomErrorFunc;
50
const DeviceInOSUExpected: CustomErrorFunc;
51
const DeviceHalted: CustomErrorFunc;
52
const UnexpectedBootloader: CustomErrorFunc;
53
const DeviceShouldStayInApp: CustomErrorFunc;
54
```
55

56
**Usage Examples:**
57

58
```typescript
59
import { 
60
  DeviceOnDashboardExpected,
61
  DeviceOnDashboardUnexpected,
62
  DeviceInOSUExpected,
63
  DeviceHalted
64
} from "@ledgerhq/errors";
65

66
// Validate device is on dashboard
67
if (!isOnDashboard) {
68
  throw new DeviceOnDashboardExpected("Please navigate to the dashboard on your device");
69
}
70

71
// Handle unexpected dashboard state
72
if (isOnDashboard && needsAppOpen) {
73
  throw new DeviceOnDashboardUnexpected("Please open the required app on your device");
74
}
75

76
// OSU mode requirement
77
if (!isInOSUMode) {
78
  throw new DeviceInOSUExpected("Device must be in OS Update mode");
79
}
80

81
// Handle halted device
82
if (deviceStatus === "halted") {
83
  throw new DeviceHalted("Device is in halted state and cannot process requests");
84
}
85
```
86

87
### Device Authenticity Errors
88

89
Errors related to device authenticity and security validation.
90

91
```typescript { .api }
92
const DeviceNotGenuineError: CustomErrorFunc;
93
const GenuineCheckFailed: CustomErrorFunc;
94
const DeviceGenuineSocketEarlyClose: CustomErrorFunc;
95
const MCUNotGenuineToDashboard: CustomErrorFunc;
96
```
97

98
**Usage Examples:**
99

100
```typescript
101
import { 
102
  DeviceNotGenuineError,
103
  GenuineCheckFailed,
104
  DeviceGenuineSocketEarlyClose
105
} from "@ledgerhq/errors";
106

107
// Handle non-genuine device
108
try {
109
  await verifyDeviceGenuine();
110
} catch (error) {
111
  if (error instanceof DeviceNotGenuineError) {
112
    console.log("Device failed authenticity check");
113
    console.log("Please ensure you are using a genuine Ledger device");
114
  }
115
}
116

117
// General genuine check failure
118
throw new GenuineCheckFailed("Unable to verify device authenticity");
119

120
// Socket closed during genuine check
121
throw new DeviceGenuineSocketEarlyClose("Connection closed during authenticity verification");
122
```
123

124
### Device Configuration Errors
125

126
Errors related to device naming and configuration.
127

128
```typescript { .api }
129
const DeviceNameInvalid: CustomErrorFunc;
130
const UserRefusedDeviceNameChange: CustomErrorFunc;
131
```
132

133
**Usage Examples:**
134

135
```typescript
136
import { 
137
  DeviceNameInvalid,
138
  UserRefusedDeviceNameChange
139
} from "@ledgerhq/errors";
140

141
// Validate device name
142
function validateDeviceName(name: string) {
143
  if (!name || name.length > 20 || /[^a-zA-Z0-9\s]/.test(name)) {
144
    throw new DeviceNameInvalid("Device name must be 1-20 alphanumeric characters");
145
  }
146
}
147

148
// Handle user refusal to change name
149
try {
150
  await changeDeviceName("My Ledger");
151
} catch (error) {
152
  if (error instanceof UserRefusedDeviceNameChange) {
153
    console.log("User cancelled device name change");
154
  }
155
}
156
```
157

158
### Hardware Reset Errors
159

160
Errors related to hardware reset operations.
161

162
```typescript { .api }
163
const HardResetFail: CustomErrorFunc;
164
```
165

166
**Usage Examples:**
167

168
```typescript
169
import { HardResetFail } from "@ledgerhq/errors";
170

171
// Handle hard reset failure
172
try {
173
  await performHardReset();
174
} catch (error) {
175
  throw new HardResetFail("Device hard reset operation failed");
176
}
177
```