A
ashfana
Guest
We had an issue where WAS service was unable to start with error data is invalid
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We checked the procmon and we could see that Service is trying to read the apphost.config file and nothing happens after that
4:45:05.6132558 PM svchost.exe 31736 41848 QueryAttributeInformationVolume C:\Windows\System32\inetsrv\config\applicationHost.config SUCCESS FileSystemAttributes: Case Preserved, Case Sensitive, Unicode, ACLs, Compression, Named Streams, EFS, Object IDs, Reparse Points, Sparse Files, Quotas, Transactions, 0x3c00600, MaximumComponentNameLength: 255, FileSystemName: NTFS NT AUTHORITY\SYSTEM 0
4:45:05.6133179 PM svchost.exe 31736 41848 QueryRemoteProtocolInformation C:\Windows\System32\inetsrv\config\applicationHost.config INVALID PARAMETER NT AUTHORITY\SYSTEM 0
4:45:05.6133488 PM svchost.exe 31736 41848 QuerySecurityFile C:\Windows\System32\inetsrv\config\applicationHost.config SUCCESS Information: Attribute NT AUTHORITY\SYSTEM 0
4:45:05.6135904 PM svchost.exe 31736 41848 ReadFile C:\Windows\System32\inetsrv\config\applicationHost.config SUCCESS Offset: 0, Length: 131,072, Priority: Normal NT AUTHORITY\SYSTEM 0
4:45:05.6137492 PM svchost.exe 31736 41848 ReadFile C:\Windows\System32\inetsrv\config\applicationHost.config SUCCESS Offset: 131,072, Length: 95,532 NT AUTHORITY\SYSTEM 0
4:45:05.6140994 PM svchost.exe 31736 41848 CloseFile C:\Windows\System32\inetsrv\config\applicationHost.config SUCCESS NT AUTHORITY\SYSTEM 0
We checked the apphost.config file and understood that we had a null parameter getting added which corrupts the apphost.config file… removing that lines resolved the issue .
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C:\WINDOWS\system32>net start WAS
The Windows Process Activation Service service is starting.
The Windows Process Activation Service service could not be started.
A system error has occurred.
System error 13 has occurred.
The data is invalid.
Removing the last line “null” from the same apphost.config I was able to start the WAS service
C:\WINDOWS\system32>net start WAS
The Windows Process Activation Service service is starting.
The Windows Process Activation Service service was started successfully.
so someone/some process is corrupting the apphost by passing null parameter
possible causes which I can think of:
in order to find the actual case ,
Continue reading...
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We checked the procmon and we could see that Service is trying to read the apphost.config file and nothing happens after that
4:45:05.6132558 PM svchost.exe 31736 41848 QueryAttributeInformationVolume C:\Windows\System32\inetsrv\config\applicationHost.config SUCCESS FileSystemAttributes: Case Preserved, Case Sensitive, Unicode, ACLs, Compression, Named Streams, EFS, Object IDs, Reparse Points, Sparse Files, Quotas, Transactions, 0x3c00600, MaximumComponentNameLength: 255, FileSystemName: NTFS NT AUTHORITY\SYSTEM 0
4:45:05.6133179 PM svchost.exe 31736 41848 QueryRemoteProtocolInformation C:\Windows\System32\inetsrv\config\applicationHost.config INVALID PARAMETER NT AUTHORITY\SYSTEM 0
4:45:05.6133488 PM svchost.exe 31736 41848 QuerySecurityFile C:\Windows\System32\inetsrv\config\applicationHost.config SUCCESS Information: Attribute NT AUTHORITY\SYSTEM 0
4:45:05.6135904 PM svchost.exe 31736 41848 ReadFile C:\Windows\System32\inetsrv\config\applicationHost.config SUCCESS Offset: 0, Length: 131,072, Priority: Normal NT AUTHORITY\SYSTEM 0
4:45:05.6137492 PM svchost.exe 31736 41848 ReadFile C:\Windows\System32\inetsrv\config\applicationHost.config SUCCESS Offset: 131,072, Length: 95,532 NT AUTHORITY\SYSTEM 0
4:45:05.6140994 PM svchost.exe 31736 41848 CloseFile C:\Windows\System32\inetsrv\config\applicationHost.config SUCCESS NT AUTHORITY\SYSTEM 0
We checked the apphost.config file and understood that we had a null parameter getting added which corrupts the apphost.config file… removing that lines resolved the issue .
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C:\WINDOWS\system32>net start WAS
The Windows Process Activation Service service is starting.
The Windows Process Activation Service service could not be started.
A system error has occurred.
System error 13 has occurred.
The data is invalid.
Removing the last line “null” from the same apphost.config I was able to start the WAS service
C:\WINDOWS\system32>net start WAS
The Windows Process Activation Service service is starting.
The Windows Process Activation Service service was started successfully.
so someone/some process is corrupting the apphost by passing null parameter
possible causes which I can think of:
- if apphost is on shared config or network share there can be disk corruption leading to this kind of issue
- i have also seen some scenarios like this when the disk gets corrupted, memory level corruptions etc can lead to config file corruption
- some scanning software /AV scanning the config folder corrupts it
in order to find the actual case ,
- we need procmon with filter set to apphost.config path to see who is touching those files
- and file level auditing for config folder
- ensure AV is not scanning IIS files/config files
Continue reading...