Question: The title says it all. Just to add that the number can be multiple digits.

I'm using the following function:

```
str_replace( "/^\&DaysAgo=d+$/", "", $save_query);

```

Answer: 
After the default installation of 8.0 Update 4 you need to run mongo manually. 

The easiest way is to install mongo by default and run it from command prompt as: mongod.exe --dbpath c:\example\_of\_my\_mongo\_database\_dir 

The best way is to install it as a windows service - <http://mikerobbins.co.uk/2015/02/02/install-mongodb-as-a-windows-service-for-sitecore/>

As soon as you do that - you'll be able to install the packages without any problem.
If the Sitecore package zip never finishes installation:
There was a log entry entry: “Job started: WatchStatus”. This Job never ended.

The package is being stored in a temporary folder on my local machine, and instead of running under the NETWORK SERVICE account that the website uses, it runs with IIS\_IUSRS role which did not have modify permissions. I granted modify permissions to this role and the package created as expected.