Network Lock crashes Avast Internet Sucurity 7.0.1426

I just installed the trial version of Avast Internet Security 7.0 yesterday, tried to enable the Network Lock and this is what I get…
Event Type: Error
Event Source: Application Error
Event Category: None
Event ID: 1000
Date: 5/24/2012
Time: 8:06:14 AM
User: N/A
Computer: MINE
Description:
Faulting application avastui.exe, version 7.0.1426.0, faulting module afwcoreclient.dll, version 7.0.1426.0, fault address 0x0000cc18.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: 41 70 70 6c 69 63 61 74 Applicat
0008: 69 6f 6e 20 46 61 69 6c ion Fail
0010: 75 72 65 20 20 61 76 61 ure ava
0018: 73 74 75 69 2e 65 78 65 stui.exe
0020: 20 37 2e 30 2e 31 34 32 7.0.142
0028: 36 2e 30 20 69 6e 20 61 6.0 in a
0030: 66 77 63 6f 72 65 63 6c fwcorecl
0038: 69 65 6e 74 2e 64 6c 6c ient.dll
0040: 20 37 2e 30 2e 31 34 32 7.0.142
0048: 36 2e 30 20 61 74 20 6f 6.0 at o
0050: 66 66 73 65 74 20 30 30 ffset 00
0058: 30 30 63 63 31 38 0d 0a 00cc18…

Any answers? Thanks