Some WEPOS 1.1 SP3 users have reported that .NET Framework 3.5 SP1 may fail to install successfully on WEPOS 1.1 SP3. And, the user may see the error “Microsoft .NET Framework 3.5 SP1 has encountered a problem during setup. Setup did not complete correctly.”

The cause of this issue is WIC (Windows Imaging Component) failing to upgrade successfully during .NET Framework 3.5 SP1 setup. .NET Framework 3.5 SP1 installation depends on WIC upgrading successfully. This issue is the same as previously blogged for an installation of .Net 3.0 or 3.0 SP1.

If you encounter this issue, it is best resolved by using the workaround described below. Please note you have to be logged in an account with Administrator privileges on the system.

1. Click Start, click Run, and type cmd.
2. On the command window prompt, type cd \Windows\system32.
3. Type regsvr32 /u wmphoto.dll.
4. Then type ren wmphoto.dll wmphoto.dll.old.
5. Then run the .NET 3.5 Installer.
6. .NET Framework 3.5 SP1 should now install successfully.

- Ankur