From the KnowledgeBase

Title:
Windows 95: Device ios causes windows protection error
During reboot, Windows 95 fails to load and gives the following message: 'while initializing device ios: windows protection error. you need to restart your computer.' The computer will then run only in safe mode. The following solution is taken from the Microsoft Knowledge Base (Q157924).

To have the computer boot up normally:
1. Boot Windows 95 in Safe mode or to a command prompt.
2. Perform one of the following two steps:
- Edit the Config.sys and Autoexec.bat files and disable any references to Smartdrv.exe.
To disable a line, type rem at the beginning of the line.
- Rename Smartdrv.exe to another name.

If your computer is a Dell, you might want to try the following fix found on Dell's file library website:
          http://support.dell.com/us/en/filelib/download/index.asp?fileid=R19318
The patch works for most models and should resolve the problem once it is installed.
Last Updated:
October 27, 2000

Solution ID:
4736