setupx.dll

SYMPTOMS
After you install Windows 98 Second Edition, you may be notified by the System File Checker tool (SFC) that the Setupx.dll file is corrupted.

CAUSE
This issue can occur if the verification table that SFC uses is not current.
RESOLUTION
To resolve this issue, use the appropriate method:

Update the Verification Table
When the Changed Files dialog box appears, click Update verification information , and then click OK .

Extract a New Setupx.dll File
If you are not sure if the file is actually corrupted, extract a new version of the file from the Windows 98 Second Edition CD-ROM.

For information about how to use System File Checker to extract a file, please see the following article in the Microsoft Knowledge Base:
Q129605 How to Extract Original Compressed Windows Files