To this error is also normally linked to the ISA managed control service not starting correctly and errors as the following in the application event viewer:
On the other hand it is also possible to hit the above error “setup failed while registering Forefront TMG managed performance monitor” as a consequence of a troubleshooting to fix a “down” of the ISA managed control service as it was in our case.
Unfortunately both errors are not really self-explicative and especially if the TMG box has installed on top of it the Edge role of exchange and the Forefront protection for exchange the very first temptation is to remove everything and reinstall all. This can mainly waste a lot of our time without any final benefit if we are under the condition of our blog post. In fact the above errors are not linked to any specific wrong condition of one of the component installed under TMG (an input string error as per above screenshot could mislead us).
As per our case the issue is very probably linked to a possible corruption in the performance monitor counters of the OS.
The solution in our case was rather straightforward and at the same time simple. For some reasons we got a corruption in the performance monitor files. This can be because of many different reasons but the most probable one as per our case is a power loss/blue screen.
To fix this apparently very bad issue it is enough to run the following command after moving under windows\system32:
The command updates registry values related to performance counters and the option /R rebuilds the performance registry strings and info from scratch based on the current registry settings and backup INI files.
That’s all. We have successfully fixed the corruption error linked to the performance counters that had as back effect to prevent the correct startup of the ISA managed control service.
We are now able to bring the ISA managed control service up and running normally.
Author Andrea Vescovo Support Engineer Microsoft CSS Forefront Edge Team
Technical Reviewer Philipp Sand Support Escalation Engineer Microsoft CSS Forefront Edge Team