In some cases, it may be useful to get information about the patch file before applying it. Simply setting the FileName property will cause the control to attempt to access the patch file if it exists. If the patch file can be opened, then the Valid property is set to True. If the patch file does not exist, has expired, or the specified password is incorrect, the property will be set to False. One common use of this property is to determine if the password for a patch file is correct:

' Determines if a patch file requires a password

PatchFile1.FileName = "house.pat"
PatchFile1.Password = "secret"

If PatchFile1.Valid Then
    ' The patch file exists and the password is valid
Else
    ' The patch file does not exist, or the password
    ' that was provided is incorrect
End If

If the patch file is valid, then the Expires property can be used to determine the number of days that the patch will remain valid. A value of zero specifies that the patch never expires. The Level property will return the patch level that was used to create the patch, and the Compression property returns the compression ratio for the patch file, as an integer value between 0 and 100.