[BarneyH343]

Always connected to wifi at home, but sometime I get UMA and sometimes I don't nothing changes as far as I know...

[Reed McLay]

Best guess, it is a carrier issue.

When you fail to acquire UMA:

Connections / Wifi Options. Menu / Wifi Diagnostics.

Note the Wifi connection details first, there should be a successful connection message.

Scroll down to UMA and note the error message. That should help to clarifiy the source of the failure.

[cavingjan]

Available bandwidth? If you network is clogged, it might not meet the bandwidth requirements. (Note: bandwidth not only means what is on your WiFi network but also is affected by the ISP load as can happen at times with cable modems that share bandwidth.)

[BarneyH343]

Connection Pref: Wi-fi preferred
UMA Wi-fi Available: Green Tick
Connection: Red cross
Error Code:
Status: Unknown error encountered

[mark-d]

I have the same issue although mine is not just at home.

I have had Orange UK UMA connection successfully both at home and at work using Plus Net broadband at home and BT Broadband at work yet since yesterday evening neither has connected.

I get the brilliant white Wi-Fi connection so get data via Wi-Fi but neither connection gives me UMA.

Diagnostics report:
Wi-Fi
Current Profile: Work
SSID: BT Fusion-9968
AP MAC Address: 00:1A:C4:E3:3A:83
Security Type: Pre-Shared Key (PSK)
Local IP Address: 192.168.178.73
Signal Level: -71 dBm
Connection Data Rate: 54 Mbps
Status: Network acquired

VPN
Current Profile:
Concentrator Address:
Contact: N/A
Authentication: N/A
Secure Device IP:
Status: VPN profile is not found.

UMA
Connection Pref.: Wi-Fi Preferred
UMA Wi-Fi Available: Successful
Connection: Error
Error Code:
Status: Establishing UMA connection...

BlackBerry Infrastructure
Connecting: Successful
Authenticating router: Successful
Authenticating server: Successful

That's all I get now either at home or at work (obviously with the different Wi_Fi details but the UMA section is the same)