If you are receiving alerts from Operations Manager where the subject looks something like this:

Subject: =?utf-8?BTG95YWx0eSBXZWIgKFNvZigaXMgbm90IHJlc3BvbmRpbmcuIC0gTG95YWx0eVdlYiBMb2dnaW5nIG9uIERMMUdTUFdFQjMxLmdhbWVzdG9wLm…

You may be seeing an issue that we ran into. We use custom channels where we define that the email subject includes the name of the alert, content from a custom field, and the name of the entity. We found that if the text is too long for the subject the subscription sends but the subject line becomes garbage. To avoid this we needed to shorten what was included in the subject line that we defined for the channel. In our case the alert name was too long so we shortened it and our subject lines on the corresponding alerts worked as expected. I have seen as many of 125 characters sent successfully on the subject line – not sure what the limit is but it seems likely to be 255 characters.

Summary: Is your subject line on OpsMgr alerts showing up as garbage? Check the length of the text which is being included in the channel / you may need to make shorten the text in the subject line.