The error you getting cannot be taken as cause but could be.
You need to enable the log level for your OM, you can use following server manager command for same and then review resulting log:
srvrmgr > change evtloglvl %=5 for comp <om_alias>
You also need to verify SWSE logs as well.
Also confirm if you have installed Siebel Release 8.1.1 BASE as installShield software or OUI ?
Just to install Siebel base 8.1.1,OUI installer is not supported.
InstallShield software need to be used, to get that login to My Oracle Support (MOS) under the Patches and Updates link,
Patch ID = 15892740
Patch 8.1.1 21111: 8.1.1 21111 SIA sebl_aru InstallShield
Have you deployed the new SRF, with the OpenUI objects in place? This is the most common reason for a 'blank' page when connecting to an OpenUI enabled OM.
The error is not the correct one to provide the information. I feel it can be an issue with your IE settings and application compatibility if are there any.
I had seen such kind of issues with the application compatibility.
Also, check whether you are able to restart of IIS services.