N8 System Error when installing apps

Question

I'm continously getting a 'System error' message whenever I try to install some apps, such as Nokia Battery Monitor, Youtube Downloader and fMobi. This occurence only began recently after updating to Symbian Anna. I've installed many other apps and can still install other apps but I seem to have a problem with a select few. I have attempted to uninstall and reinstall the apps and also done a delete and restore after backup but still no change.
Thanks in advance for any suggestions 
Nokia N8 - Symbian Anna  - 059C5Q8 - Unbranded - UK

Answer 1

I did the update yesterday via OVI.........
I get a "system error" message every time the phone starts
Can't get into my contacts at all, the timer pops up and then goes away! (There are 260 in memory and SPB Shell has access!!!)
Conversations won't run, says not available feature
Can't install the beta labs sleeping screen
Took multiple attempts to install OVI chat
All I want is a working phone!  It was working better before the damn update!
It looks like there's something missing after the update 
Tried *#7370# for return to factory defaults, no change
Tried re-installing Anna, no change
Anyone else having these issues too? Any solutions you can think of?
This is a UK UNBRANDED N8 bought directly from Nokia in Finland
Software version 022.014
Custom version 022.014.226.06
N8 (059C5Q5) now running Belle V111.030.0609
N8 (059C5Q5) previously running Anna V25.007
Previous [N97, N95 8Gb, N95, N82]
If in doubt, RTFM! (Read The F***ing Manual)