tsvn and the mbr

Does tsvn (or svn) write to the Master Boot Record of the device it's installed on?

Here is why I ask:
Friday at work : I instal tsvn on a removable hard drive [in caddy] in my work pc (XP SP2)
Saturday at home: Use the same drive in my home PC as always do no problems
Sunday at home : same thing
Monday at work : insert caddy as usual, check mail etc for 5 minutes, browse the folder where a I have tsvn and a copy of a repository and BANG I get a tsvn error regarding disk access (even though I did not use it explicitly) and since then I the MBR of my disk seems corrupt.

I have used a caddy for 8 years now without a problem. I am just wondering if tsvn did not trip over itself because it is in a drive that gets accessed by 2 different PCs.

Currently trying to recover data : 10 hours and counting [getdatback + instally recovery console on xp)

-- 
Chris at home.
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There are only 10 types of people in this world; 
  those who understand binary and those who don't.
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