I have added a couple of mods to my F900BT so I am ok with testmode etc.I tried to install the official 2.009 pioneer upgrade but just get stuck in the start up loop.I also tried installing the 3.00 upgrade from here with the same results.Can anyone tell me what I am doing wrong? 
You propably tried to install 2.09 over your mods, depending on the mods this can brick your unit.
Use this: viewtopic.php?f=33&t=25424&p=173323&hilit=dismount#p173323
step by step to get your system to a clean 2.xxxx.
I hope you have your flashdisk backup (without the mods) on hand.
Once you have done this you should be able to install 3.0
See you
Jörg
Thank you.Unfortunately i only backed up my flash drive AFTER i had installed CMH's mod unziptosdcard.I will try to DL a clean V2 as you suggest.Thank you again.
Use the CE Image from your backup, there are a lot of wrong images floating around, maybe you can just use your Flashdisk and replace only the modded files with downloaded ones. then you should be good
Good Luck
Jörg
Thanks Jorg but no luck.Have posted another cry for help hoping someone has had the same problem 
This problem is caused usually by nav part, so problem is most likely in APL2\IGO-folder. If you have clean installation files, try to delete this folder from your flash disk and then copy clean one to flash disk. If you just copy new folder it doesn't overwrite existing folders completely; if there's files in existing folder which aren't in folder being copied, those "extra" files are left to flash disk, which may cause problems. I found this by myself when I copied corrupted speedcam.txt-file to my flash disk; my avic stuck on "system startup in progress"-message, even when I copied original backup if APL\IGO-folder, it didnt fix the problem as this corrupted file was still present. Also try to delete files in user\userdata\igo-folder.
First make sure you have the original license file (the one comes with your device) in the license folder.
To find out why it stucks, just run the ezrider.exe within TestMode. Most time, "System start up in progress" problem can be fixed very easily.