I am having the same problem. Here is my log to see if it will help.
********* FSUIPC4, Version 4.743 by Pete Dowson *********
User Name="Jon Verrett"
User Addr="jcverrett@gmail.com"
FSUIPC4 Key is provided
WideFS7 Key is provided
Running inside FSX on Windows 7
Module base=61000000
Wind smoothing fix is not installed
DebugStatus=255
468 System time = 26/10/2011 09:24:26
468 FLT UNC path = "\\DADS-PC\Users\Jon Verrett\Documents\Flight Simulator X Files\"
514 Trying to connect to SimConnect Acc/SP2 Oct07 ...
514 FS UNC path = "D:\Microsoft Flight Simulator X\"
1201 Run: "D:\Microsoft Flight Simulator X\Modules\linda.exe"
1232 LogOptions=10000000 00000001
1232 VRI port 1 "com3" failed to open
1232 SimConnect_Open succeeded: waiting to check version okay
1232 Trying to use SimConnect Acc/SP2 Oct07
3447 Running in "Microsoft Flight Simulator X", Version: 10.0.61637.0 (SimConnect: 10.0.61259.0)
3447 Initialising SimConnect data requests now
3447 FSUIPC Menu entry added
3478 \\DADS-PC\Users\Jon Verrett\Documents\Flight Simulator X Files\Default.FLT
3478 D:\Microsoft Flight Simulator X\SimObjects\Airplanes\C172\Cessna172SP.AIR
26052 D:\Microsoft Flight Simulator X\SimObjects\Airplanes\VRS_FA-18E\FA-18E-6.8_SE.AIR
66097 Exception 3 "UNRECOGNIZED_ID", Ref 2374, Index param 1 on write SetData for "GENERAL ENG THROTTLE LEVER POSITION:1"
66097 Exception 3 "UNRECOGNIZED_ID", Ref 2375, Index param 1 on write SetData for "GENERAL ENG THROTTLE LEVER POSITION:2"
66409 *** AXIS: Cntrl= 65786 (0x000100fa), Param= 228 (0x000000e4) SPOILERS_SET
66596 System time = 26/10/2011 09:25:32, Simulator time = 09:24:30 (14:24Z)
66815 Aircraft="VFA-31 "Tomcatters" Line"
70528 Starting everything now ...
70543 LUA: beginning "D:\Microsoft Flight Simulator X\Modules\ipcReady.lua"
70543 LUA: ended "D:\Microsoft Flight Simulator X\Modules\ipcReady.lua"
70543 LUA:
70543 LUA: [iNIT]LINDA:: Loading...
70621 LUA: LINDA:: Aircraft: VFA-31 "Tomcatters" Line
70637 LUA: LINDA:: Aircraft module detected: VRS F18
70684 LUA: LINDA:: AivlaSoft library loaded...
70684 LUA: LINDA:: FSX standard library loaded...
70699 LUA: LINDA:: RealityXP library loaded...
70699 LUA: LINDA:: A2A MAP library loaded...
70793 LUA: LINDA:: DSP MODE toggle: 2
70808 LUA: LINDA:: ---> ERROR:: Could not open MCP Combo port!
70808 LUA: LINDA:: Loading a fallback joysticks config...
70824 LUA: LINDA:: Loading VRS F18 joysticks config...
70824 LUA: LINDA:: Module: VRS F18 Started...
70824 LUA: LINDA:: Ready to go, Captain!
70824 LUA: LINDA::
70855 LUA: LINDA:: Offsets watching list cleared!
73398 Advanced Weather Interface Enabled
94380 Sim stopped: average frame rate for last 28 secs = 21.6 fps
104099 System time = 26/10/2011 09:26:10, Simulator time = 09:24:56 (14:24Z)
104099 *** FSUIPC log file being closed
Average frame rate for running time of 28 secs = 21.6 fps
Memory managed: 51 Allocs, 51 Freed
********* FSUIPC Log file closed ***********
Hope this is helpful Pete.