I use Freedom Scientific JAWS 15 on two of my Windows PC and haven’t encountered any issues.
Looking at the error it seems your avast has gone corrupt:
There’s 2 ways to use the uninstall tool:
- Run in safe mode (which you can’t since JAWS wouldn’t work)
- Disable avast! self defence through avast! UI > Settings > Troubleshooting
#2 will then enable you to run the removal tool in normal mode.
After you have run that tool, it’s best to run this tool to clear some files avastclear may miss.
Links:
Avastclear : http://files.avast.com/iavs9x/avastclear.exe
Rejzors Uninstall tool: http://rejzor.wordpress.com/avast-cleanup-tool/
Once you get it removed, it’s up to you if you wish to try avast! again since there isn’t any issues with screen readers.
On another note, if you remove JAWS from one PC and put it on another new one, you can use the same license.